Sample records for tomography muon tomography

  1. Imaging and sensing based on muon tomography

    DOE Patents [OSTI]

    Morris, Christopher L; Saunders, Alexander; Sossong, Michael James; Schultz, Larry Joe; Green, J. Andrew; Borozdin, Konstantin N; Hengartner, Nicolas W; Smith, Richard A; Colthart, James M; Klugh, David C; Scoggins, Gary E; Vineyard, David C

    2012-10-16T23:59:59.000Z

    Techniques, apparatus and systems for detecting particles such as muons for imaging applications. Subtraction techniques are described to enhance the processing of the muon tomography data.

  2. High Resolution Muon Computed Tomography at Neutrino Beam Facilities

    E-Print Network [OSTI]

    Suerfu, Burkhant

    2015-01-01T23:59:59.000Z

    X-ray computed tomography (CT) has an indispensable role in constructing 3D images of objects made from light materials. However, limited by absorption coefficients, X-rays cannot deeply penetrate materials such as copper and lead. Here we show via simulation that muon beams can provide high resolution tomographic images of dense objects and of structures within the interior of dense objects. The effects of resolution broadening from multiple scattering diminish with increasing muon momentum. As the momentum of the muon increases, the contrast of the image goes down and therefore requires higher resolution in the muon spectrometer to resolve the image. The variance of the measured muon momentum reaches a minimum and then increases with increasing muon momentum. The impact of the increase in variance is to require a higher integrated muon flux to reduce fluctuations. The flux requirements and level of contrast needed for high resolution muon computed tomography are well matched to the muons produced in the pio...

  3. High Resolution Muon Computed Tomography at Neutrino Beam Facilities

    E-Print Network [OSTI]

    Burkhant Suerfu; Christopher G. Tully

    2015-01-28T23:59:59.000Z

    X-ray computed tomography (CT) has an indispensable role in constructing 3D images of objects made from light materials. However, limited by absorption coefficients, X-rays cannot deeply penetrate materials such as copper and lead. Here we show via simulation that muon beams can provide high resolution tomographic images of dense objects and of structures within the interior of dense objects. The effects of resolution broadening from multiple scattering diminish with increasing muon momentum. As the momentum of the muon increases, the contrast of the image goes down and therefore requires higher resolution in the muon spectrometer to resolve the image. The variance of the measured muon momentum reaches a minimum and then increases with increasing muon momentum. The impact of the increase in variance is to require a higher integrated muon flux to reduce fluctuations. The flux requirements and level of contrast needed for high resolution muon computed tomography are well matched to the muons produced in the pion decay pipe at a neutrino beam facility and what can be achieved for momentum resolution in a muon spectrometer. Such an imaging system can be applied in archaeology, art history, engineering, material identification and whenever there is a need to image inside a transportable object constructed of dense materials.

  4. Discussion - Next Step for Fukushima Daiichi Muon Tomography

    SciTech Connect (OSTI)

    Miyadera, Haruo [Los Alamos National Laboratory

    2012-08-13T23:59:59.000Z

    Specification of Fukushima Daiichi Muon Tomography (FMT): (1) 18-feet (5.5-m) drift tube, 2-inch (5-cm) diameter; (2) 108 tubes per layer; (3) Unit layer = 2 layer (detection efficiency: 0.96 x 0.96 = 92%); (4) 12 or 16 layer per module; (5) 16 layers allows momentum analysis at 30% level; (6) 2 module per super module (5.5 x 11 m{sup 2}); and (7) FMT = 2 super module. By deploying MMT next to a research reactor, we will be able to measure the impact of low level radiation fields on muon tomography and reconstruction processes. Radiation level during reactor operation is {approx}50 {micro}Sv/h which provides similar radiation environment of inside the FMT radiation shield at Fukushima Daiichi. We will implement coincidence algorithm on the FPGA board.

  5. Our Next Two Steps for Fukushima Daiichi Muon Tomography

    SciTech Connect (OSTI)

    Miyadera, Haruo [Los Alamos National Laboratory

    2012-04-11T23:59:59.000Z

    After the vast disasters caused by the great earthquake and tsunami in eastern Japan, we proposed applying our Muon Tomography (MT) technique to help and improve the emergency situation at Fukushima Daiichi using cosmic-ray muons. A reactor-tomography team was formed at LANL which was supported by the Laboratory as a response to a request by the former Japanese Prime Minister, Naoto Kan. Our goal is to help the Japanese people and support remediation of the reactors. At LANL, we have carried out a proof-of-principle technical demonstration and simulation studies that established the feasibility of MT to image a reactor core. This proposal covers the next two critical steps for Fukushima Daiichi Muon Imaging: (1) undertake case study mock-up experiments of Fukushima Daiichi, and (2) system optimization. We requested funding to the US and Japanese government to assess damage of reactors at Fukushima Daiichi. The two steps will bring our project to the 'ready-to-go' level.

  6. A range muon tomography performance study for the detection of explosives

    SciTech Connect (OSTI)

    Cuellar, Leticia [Los Alamos National Laboratory; Borozdin, Konstantin N [Los Alamos National Laboratory; Chung, Andrew [Los Alamos National Laboratory; Nicolas, Hengartner W [Los Alamos National Laboratory; Morris, Christopher [Los Alamos National Laboratory; Schultz, Larry J [Los Alamos National Laboratory; Reimus, Nathaniel P [Los Alamos National Laboratory; Bacon, Jeffrey D [Los Alamos National Laboratory; Vogan - Mc Neil, Wendy [Los Alamos National Laboratory

    2010-01-01T23:59:59.000Z

    Soft cosmic ray tomography has been shown to successfully discriminate materials with various density levels due to their ability to deeply penetrate matter, allowing sensitivity to atomic number, radiation length and density. Because the multiple muon scattering signal from high Z-materials is very strong, the technology is well suited to the detection of the illicit transportation of special and radiological nuclear materials. In addition, a recent detection technique based on measuring the lower energy particles that do not traverse the material (range radiography), allows to discriminate low and medium Z-materials. This is shown in [4] using Monte Carlo simulations. More recently, using a mini muon tracker developed at Los Alamos National Laboratory, we performed various experiments to try out the radiation length technology. This paper presents the results from real experiments and evaluates the likelihood that soft cosmic ray tomography may be applied to detect high-explosives.

  7. Nuclear Waste Imaging and Spent Fuel Verification by Muon Tomography

    E-Print Network [OSTI]

    Jonkmans, G; Jewett, C; Thompson, M

    2012-01-01T23:59:59.000Z

    This paper explores the use of cosmic ray muons to image the contents of shielded containers and detect high-Z special nuclear materials inside them. Cosmic ray muons are a naturally occurring form of radiation, are highly penetrating and exhibit large scattering angles on high Z materials. Specifically, we investigated how radiographic and tomographic techniques can be effective for non-invasive nuclear waste characterization and for nuclear material accountancy of spent fuel inside dry storage containers. We show that the tracking of individual muons, as they enter and exit a structure, can potentially improve the accuracy and availability of data on nuclear waste and the contents of Dry Storage Containers (DSC) used for spent fuel storage at CANDU plants. This could be achieved in near real time, with the potential for unattended and remotely monitored operations. We show that the expected sensitivity, in the case of the DSC, exceeds the IAEA detection target for nuclear material accountancy.

  8. Characterising encapsulated nuclear waste using cosmic-ray muon tomography

    E-Print Network [OSTI]

    Clarkson, Anthony; Hoek, Matthias; Ireland, David G; Johnstone, John R; Kaiser, Ralf; Keri, Tibor; Lumsden, Scott; Mahon, David F; McKinnon, Bryan; Murray, Morgan; Nutbeam-Tuffs, Siân; Shearer, Craig; Yang, Guangliang; Zimmerman, Colin

    2014-01-01T23:59:59.000Z

    Tomographic imaging techniques using the Coulomb scattering of cosmic-ray muons have been shown previously to successfully identify and characterise low- and high-Z materials within an air matrix using a prototype scintillating-fibre tracker system. Those studies were performed as the first in a series to assess the feasibility of this technology and image reconstruction techniques in characterising the potential high-Z contents of legacy nuclear waste containers for the UK Nuclear Industry. The present work continues the feasibility study and presents the first images reconstructed from experimental data collected using this small-scale prototype system of low- and high-Z materials encapsulated within a concrete-filled stainless-steel container. Clear discrimination is observed between the thick steel casing, the concrete matrix and the sample materials assayed. These reconstructed objects are presented and discussed in detail alongside the implications for future industrial scenarios.

  9. Characterising encapsulated nuclear waste using cosmic-ray muon tomography

    E-Print Network [OSTI]

    Anthony Clarkson; David J. Hamilton; Matthias Hoek; David G. Ireland; John R. Johnstone; Ralf Kaiser; Tibor Keri; Scott Lumsden; David F. Mahon; Bryan McKinnon; Morgan Murray; Siân Nutbeam-Tuffs; Craig Shearer; Guangliang Yang; Colin Zimmerman

    2014-10-27T23:59:59.000Z

    Tomographic imaging techniques using the Coulomb scattering of cosmic-ray muons have been shown previously to successfully identify and characterise low- and high-Z materials within an air matrix using a prototype scintillating-fibre tracker system. Those studies were performed as the first in a series to assess the feasibility of this technology and image reconstruction techniques in characterising the potential high-Z contents of legacy nuclear waste containers for the UK Nuclear Industry. The present work continues the feasibility study and presents the first images reconstructed from experimental data collected using this small-scale prototype system of low- and high-Z materials encapsulated within a concrete-filled stainless-steel container. Clear discrimination is observed between the thick steel casing, the concrete matrix and the sample materials assayed. These reconstructed objects are presented and discussed in detail alongside the implications for future industrial scenarios.

  10. Monitoring temporal opacity fluctuations of large structures with muon tomography : a calibration experiment using a water tower tank

    E-Print Network [OSTI]

    Jourde, Kevin; Marteau, Jacques; d'Ars, Jean de Bremond; Gardien, Serge; Girerd, Claude; Ianigro, Jean-Christophe

    2015-01-01T23:59:59.000Z

    The idea of using secondary cosmic muons to scan the internal structure of a given body has known significant developments since the first archaeological application by Alvarez and collaborators on the Gizah pyramids. Recent applications cover the fields of volcanology, hydrology, civil engineering, mining, archaeology etc. Muon radiography features are essentially identical to those of medical X-ray imaging techniques. It is a contrast densitometry method using the screening effect of the body under study on the natural flux of cosmic muons. This technique is non-invasive and complements the standard geophysical techniques, e.g. electrical tomography or gravimetry. It may be applied to a large variety of geological targets, among which the domes of active volcanoes. In this context muon tomography presents the noticeable advantage to perform measurements of large volumes, with a large aperture, from a distant point, far from the potentially dangerous zones. The same conclusions apply regarding the monitoring...

  11. Monitoring temporal opacity fluctuations of large structures with muon tomography : a calibration experiment using a water tower tank

    E-Print Network [OSTI]

    Kevin Jourde; Dominique Gibert; Jacques Marteau; Jean de Bremond d'Ars; Serge Gardien; Claude Girerd; Jean-Christophe Ianigro

    2015-04-09T23:59:59.000Z

    The idea of using secondary cosmic muons to scan the internal structure of a given body has known significant developments since the first archaeological application by Alvarez and collaborators on the Gizah pyramids. Recent applications cover the fields of volcanology, hydrology, civil engineering, mining, archaeology etc. Muon radiography features are essentially identical to those of medical X-ray imaging techniques. It is a contrast densitometry method using the screening effect of the body under study on the natural flux of cosmic muons. This technique is non-invasive and complements the standard geophysical techniques, e.g. electrical tomography or gravimetry. It may be applied to a large variety of geological targets, among which the domes of active volcanoes. In this context muon tomography presents the noticeable advantage to perform measurements of large volumes, with a large aperture, from a distant point, far from the potentially dangerous zones. The same conclusions apply regarding the monitoring of the volcano's activity since muon tomography provides continuous data taking, provided the muon detectors are sufficiently well designed and autonomous. Recent measurements on La Soufri\\`ere of Guadeloupe (Lesser Antilles, France) show, over a one year period, large modulations of the crossing muon flux, correlated with an increase of the activity in the dome. In order to firmly establish the sensitivity of the method and of our detectors and to disentangle the effects on the muon flux modulations induced by the volcano's hydrothermal system from those induced by other sources, e.g. atmospheric temperature and pressure, we perform a dedicated calibration experiment inside a water tower tank. We show how the method is fully capable of dynamically following fast variations in the density.

  12. Correction to "Threedimensional computational axial tomography scan of a volcano with cosmic ray muon radiography"

    E-Print Network [OSTI]

    Aoki, Yosuke

    Correction to "Threedimensional computational axial tomography scan of a volcano with cosmic ray.1029/2011JB008256. [1] In the paper "Threedimensional computational axial tomography scan of a volcano. Aoki, R. Nishiyama, D. Shoji, and H. Tsuiji (2011), Correction to "Threedimensional computational axial

  13. Pseudolocal tomography

    DOE Patents [OSTI]

    Katsevich, Alexander J. (Los Alamos, NM); Ramm, Alexander G. (Manhattan, KS)

    1996-01-01T23:59:59.000Z

    Local tomographic data is used to determine the location and value of a discontinuity between a first internal density of an object and a second density of a region within the object. A beam of radiation is directed in a predetermined pattern through the region of the object containing the discontinuity. Relative attenuation data of the beam is determined within the predetermined pattern having a first data component that includes attenuation data through the region. The relative attenuation data is input to a pseudo-local tomography function, where the difference between the internal density and the pseudo-local tomography function is computed across the discontinuity. The pseudo-local tomography function outputs the location of the discontinuity and the difference in density between the first density and the second density.

  14. Pseudolocal tomography

    DOE Patents [OSTI]

    Katsevich, A.J.; Ramm, A.G.

    1996-07-23T23:59:59.000Z

    Local tomographic data is used to determine the location and value of a discontinuity between a first internal density of an object and a second density of a region within the object. A beam of radiation is directed in a predetermined pattern through the region of the object containing the discontinuity. Relative attenuation data of the beam is determined within the predetermined pattern having a first data component that includes attenuation data through the region. The relative attenuation data is input to a pseudo-local tomography function, where the difference between the internal density and the pseudo-local tomography function is computed across the discontinuity. The pseudo-local tomography function outputs the location of the discontinuity and the difference in density between the first density and the second density. 7 figs.

  15. Doppler Tomography

    E-Print Network [OSTI]

    T. R. Marsh

    2000-11-01T23:59:59.000Z

    I review the method of Doppler tomography which translates binary-star line profiles taken at a series of orbital phases into a distribution of emission over the binary. I begin with a discussion of the basic principles behind Doppler tomography, including a comparison of the relative merits of maximum entropy regularisation versus filtered back-projection for implementing the inversion. Following this I discuss the issue of noise in Doppler images and possible methods for coping with it. Then I move on to look at the results of Doppler Tomography applied to cataclysmic variable stars. Outstanding successes to date are the discovery of two-arm spiral shocks in cataclysmic variable accretion discs and the probing of the stream/magnetospheric interaction in magnetic cataclysmic variable stars. Doppler tomography has also told us much about the stream/disc interaction in non-magnetic systems and the irradiation of the secondary star in all systems. The latter indirectly reveals such effects as shadowing by the accretion disc or stream. I discuss all of these and finish with some musings on possible future directions for the method. At the end I include a tabulation of Doppler maps published in refereed journals.

  16. Computed tomography of cryogenic cells

    E-Print Network [OSTI]

    2001-01-01T23:59:59.000Z

    COMPUTED TOMOGRAPHY OF CRYOGENIC CELLS G. SCHNEIDER, and E.absorption, computed tomography (CT) can be performed. Sincethis work is to apply computed tomography, which has already

  17. Muon tomography imaging algorithms for nuclear threat detection inside large volume containers with the Muon Portal detector

    E-Print Network [OSTI]

    Riggi, S; Bandieramonte, M; Becciani, U; Costa, A; La Rocca, P; Massimino, P; Petta, C; Pistagna, C; Riggi, F; Sciacca, E; Vitello, F

    2013-01-01T23:59:59.000Z

    Muon tomographic visualization techniques try to reconstruct a 3D image as close as possible to the real localization of the objects being probed. Statistical algorithms under test for the reconstruction of muon tomographic images in the Muon Portal Project are here discussed. Autocorrelation analysis and clustering algorithms have been employed within the context of methods based on the Point Of Closest Approach (POCA) reconstruction tool. An iterative method based on the log-likelihood approach was also implemented. Relative merits of all such methods are discussed, with reference to full Geant4 simulations of different scenarios, incorporating medium and high-Z objects inside a container.

  18. The Design and Performance of a Scintillating-Fibre Tracker for the Cosmic-ray Muon Tomography of Legacy Nuclear Waste Containers

    E-Print Network [OSTI]

    Clarkson, Anthony; Hoek, Matthias; Ireland, David G; Johnstone, Russell; Kaiser, Ralf; Keri, Tibor; Lumsden, Scott; Mahon, David F; McKinnon, Bryan; Murray, Morgan; Nutbeam-Tuffs, Sian; Shearer, Craig; Staines, Cassie; Yang, Guangliang; Zimmerman, Colin

    2013-01-01T23:59:59.000Z

    Tomographic imaging techniques using the Coulomb scattering of cosmic-ray muons are increasingly being exploited for the non-destructive assay of shielded containers in a wide range of applications. One such application is the characterisation of legacy nuclear waste materials stored within industrial containers. The design, assembly and performance of a prototype muon tomography system developed for this purpose are detailed in this work. This muon tracker comprises four detection modules, each containing orthogonal layers of Saint-Gobain BCF-10 2mm-pitch plastic scintillating fibres. Identification of the two struck fibres per module allows the reconstruction of the incoming and Coulomb-scattered muon trajectories. These allow the container content, with respect to the atomic number Z of the scattering material, to be determined through reconstruction of the scattering location and magnitude. On each detection layer, the light emitted by the fibre is detected by a single Hamamatsu H8500 MAPMT with two fibre...

  19. Modulated Luminescent Tomography

    E-Print Network [OSTI]

    2015-01-28T23:59:59.000Z

    modalities behave differently than Photoacoustic and Thermoacoustic Tomography, where the ex- citation is highly diffusive but the emitted ultrasound signal ...

  20. Mathematics of thermoacoustic tomography

    E-Print Network [OSTI]

    Peter Kuchment; Leonid Kunyansky

    2007-10-21T23:59:59.000Z

    The paper presents a survey of mathematical problems, techniques, and challenges arising in the Thermoacoustic and Photoacoustic Tomography.

  1. GEANT4 Simulation of a Scintillating-Fibre Tracker for the Cosmic-ray Muon Tomography of Legacy Nuclear Waste Containers

    E-Print Network [OSTI]

    Clarkson, Anthony; Hoek, Matthias; Ireland, David G; Johnstone, Russell; Kaiser, Ralf; Keri, Tibor; Lumsden, Scott; Mahon, David F; McKinnon, Bryan; Murray, Morgan; Nutbeam-Tuffs, Sian; Shearer, Craig; Staines, Cassie; Yang, Guangliang; Zimmerman, Colin

    2013-01-01T23:59:59.000Z

    Cosmic-ray muons are highly penetrative charged particles that are observed at sea level with a flux of approximately one per square centimetre per minute. They interact with matter primarily through Coulomb scattering, which is exploited in the field of muon tomography to image shielded objects in a wide range of applications. In this paper, simulation studies are presented that assess the feasibility of a scintillating-fibre tracker system for use in the identification and characterisation of nuclear materials stored within industrial legacy waste containers. A system consisting of a pair of tracking modules above and a pair below the volume to be assayed is simulated within the GEANT4 framework using a range of potential fibre pitches and module separations. Each module comprises two orthogonal planes of fibres that allow the reconstruction of the initial and Coulomb-scattered muon trajectories. A likelihood-based image reconstruction algorithm has been developed that allows the container content to be det...

  2. Turbocharging Quantum Tomography.

    SciTech Connect (OSTI)

    Blume-Kohout, Robin J; Gamble, John King,; Nielsen, Erik; Maunz, Peter Lukas Wilhelm; Scholten, Travis L.; Rudinger, Kenneth Michael

    2015-01-01T23:59:59.000Z

    Quantum tomography is used to characterize quantum operations implemented in quantum information processing (QIP) hardware. Traditionally, state tomography has been used to characterize the quantum state prepared in an initialization procedure, while quantum process tomography is used to characterize dynamical operations on a QIP system. As such, tomography is critical to the development of QIP hardware (since it is necessary both for debugging and validating as-built devices, and its results are used to influence the next generation of devices). But tomography su %7C ers from several critical drawbacks. In this report, we present new research that resolves several of these flaws. We describe a new form of tomography called gate set tomography (GST), which unifies state and process tomography, avoids prior methods critical reliance on precalibrated operations that are not generally available, and can achieve unprecedented accuracies. We report on theory and experimental development of adaptive tomography protocols that achieve far higher fidelity in state reconstruction than non-adaptive methods. Finally, we present a new theoretical and experimental analysis of process tomography on multispin systems, and demonstrate how to more e %7C ectively detect and characterize quantum noise using carefully tailored ensembles of input states.

  3. Analysis of the multigroup model for muon tomography based threat detection

    SciTech Connect (OSTI)

    Perry, J. O.; Bacon, J. D.; Borozdin, K. N.; Fabritius, J. M.; Morris, C. L. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2014-02-14T23:59:59.000Z

    We compare different algorithms for detecting a 5?cm tungsten cube using cosmic ray muon technology. In each case, a simple tomographic technique was used for position reconstruction, but the scattering angles were used differently to obtain a density signal. Receiver operating characteristic curves were used to compare images made using average angle squared, median angle squared, average of the squared angle, and a multi-energy group fit of the angular distributions for scenes with and without a 5?cm tungsten cube. The receiver operating characteristic curves show that the multi-energy group treatment of the scattering angle distributions is the superior method for image reconstruction.

  4. Electron tomography of defects

    E-Print Network [OSTI]

    Sharp, Joanne

    2010-10-12T23:59:59.000Z

    . . . . . . . . . . . . . . . . . . . 36 2.6 Limitations of electron tomography . . . . . . . . . . . . . . . 37 2.6.1 The missing wedge . . . . . . . . . . . . . . . . . . . . 37 2.6.2 Minimum reliable spacing of features . . . . . . . . . . 39 3 Tomography of dislocations using weak... ELECTRON TOMOGRAPHY OF DEFECTS This dissertation is submitted for the degree of Doctor of Philosophy by Joanne Sharp Of Wolfson College Submitted 26th April 2010 Acknowledgements This dissertation is the result of my own work and includes nothing...

  5. Neutron computed tomography

    E-Print Network [OSTI]

    Russell, Clifford Marlow

    1992-01-01T23:59:59.000Z

    of tomography was discovered by Radon in 1917. Radon, a mathematician, solved the problem for an n-dimensional function with n-I dimensional projectors as related to gravitational equations. Radon's technique is not the only mathematical basis for tomography...

  6. Dual seven pinhole tomography

    SciTech Connect (OSTI)

    Bizais, Y.; Zubal, I.G.; Rowe, R.W.; Bennett, G.W.; Brill, A.B.

    1982-01-01T23:59:59.000Z

    Emission tomography using two orthogonal sets of projections through seven pinhole collimators is considered. This paper describes the acquisition system, the reconstruction algorithm, presents results obtained in phantom studies, and discusses the advantages and disadvantages of this method over conventional Seven Pinhole Tomography.

  7. GEANT4 Simulation of a Scintillating-Fibre Tracker for the Cosmic-ray Muon Tomography of Legacy Nuclear Waste Containers

    E-Print Network [OSTI]

    Anthony Clarkson; David J. Hamilton; Matthias Hoek; David G. Ireland; Russell Johnstone; Ralf Kaiser; Tibor Keri; Scott Lumsden; David F. Mahon; Bryan McKinnon; Morgan Murray; Sian Nutbeam-Tuffs; Craig Shearer; Cassie Staines; Guangliang Yang; Colin Zimmerman

    2013-09-13T23:59:59.000Z

    Cosmic-ray muons are highly penetrative charged particles that are observed at sea level with a flux of approximately one per square centimetre per minute. They interact with matter primarily through Coulomb scattering, which is exploited in the field of muon tomography to image shielded objects in a wide range of applications. In this paper, simulation studies are presented that assess the feasibility of a scintillating-fibre tracker system for use in the identification and characterisation of nuclear materials stored within industrial legacy waste containers. A system consisting of a pair of tracking modules above and a pair below the volume to be assayed is simulated within the GEANT4 framework using a range of potential fibre pitches and module separations. Each module comprises two orthogonal planes of fibres that allow the reconstruction of the initial and Coulomb-scattered muon trajectories. A likelihood-based image reconstruction algorithm has been developed that allows the container content to be determined with respect to the atomic number Z of the scattering material. Images reconstructed from this simulation are presented for a range of anticipated scenarios that highlight the expected image resolution and the potential of this system for the identification of high-Z materials within a shielded, concrete-filled container. First results from a constructed prototype system are presented in comparison with those from a detailed simulation. Excellent agreement between experimental data and simulation is observed showing clear discrimination between the different materials assayed throughout.

  8. Thermoacoustic tomography, variable sound speed Plamen Stefanov

    E-Print Network [OSTI]

    Stefanov, Plamen

    Thermoacoustic tomography, variable sound speed Plamen Stefanov Purdue University Based on a joint work with Gunther Uhlmann Plamen Stefanov (Purdue University ) Thermoacoustic tomography, variable sound speed 1 / 18 #12;Formulation Main Problem Thermoacoustic Tomography In thermoacoustic tomography

  9. Regularized Equally Sloped Tomography Algorithm for Low Dose X-Ray Computed Tomography

    E-Print Network [OSTI]

    Zhao, Yunzhe

    2012-01-01T23:59:59.000Z

    based imaging computed tomography extraction algorithms and10 2.2. Computed Tomography reconstruction theory andcontrast X-ray computed tomography for observing biological

  10. Regularized Equally Sloped Tomography Algorithm for Low Dose X-Ray Computed Tomography

    E-Print Network [OSTI]

    Zhao, Yunzhe

    2012-01-01T23:59:59.000Z

    based imaging computed tomography extraction algorithms andcontrast X-ray computed tomography for observing biological10 2.2. Computed Tomography reconstruction theory and

  11. Ionospheric Correction Using Tomography

    E-Print Network [OSTI]

    Stanford University

    re- quirements on the order of ones of meters with safety of life integrity requirements which delay algorithms. The capability of ionospheric tomography is demon- strated by a time series of 3D°N 30°N 30°N 40°N 40°N 50°N 50°N 60°N 60°N Figure 1: The NSTB reference network geometry is comprised

  12. Jet Tomography at RHIC

    E-Print Network [OSTI]

    J. C. Dunlop

    2007-07-10T23:59:59.000Z

    The status of the use of hard probes in heavy ion collisions at RHIC is reviewed. The discovery of strong jet quenching at RHIC is a major success. However, in order to make full use of this new phenomenon for full jet emission tomography of the properties of the collision zone further development is needed, both experimentally and theoretically.

  13. Enhanced local tomography

    DOE Patents [OSTI]

    Katsevich, Alexander J. (Los Alamos, NM); Ramm, Alexander G. (Manhattan, KS)

    1996-01-01T23:59:59.000Z

    Local tomography is enhanced to determine the location and value of a discontinuity between a first internal density of an object and a second density of a region within the object. A beam of radiation is directed in a predetermined pattern through the region of the object containing the discontinuity. Relative attenuation data of the beam is determined within the predetermined pattern having a first data component that includes attenuation data through the region. In a first method for evaluating the value of the discontinuity, the relative attenuation data is inputted to a local tomography function .function..sub..LAMBDA. to define the location S of the density discontinuity. The asymptotic behavior of .function..sub..LAMBDA. is determined in a neighborhood of S, and the value for the discontinuity is estimated from the asymptotic behavior of .function..sub..LAMBDA.. In a second method for evaluating the value of the discontinuity, a gradient value for a mollified local tomography function .gradient..function..sub..LAMBDA..epsilon. (x.sub.ij) is determined along the discontinuity; and the value of the jump of the density across the discontinuity curve (or surface) S is estimated from the gradient values.

  14. Thermoacoustic tomography with variable sound speed

    E-Print Network [OSTI]

    2009-10-26T23:59:59.000Z

    We study the mathematical model of thermoacoustic tomography in media with a ... In thermoacoustic tomography, a short electro-magnetic pulse is sent through ...

  15. Positron Emission Tomography (PET)

    DOE R&D Accomplishments [OSTI]

    Welch, M. J.

    1990-01-00T23:59:59.000Z

    Positron emission tomography (PET) assesses biochemical processes in the living subject, producing images of function rather than form. Using PET, physicians are able to obtain not the anatomical information provided by other medical imaging techniques, but pictures of physiological activity. In metaphoric terms, traditional imaging methods supply a map of the body's roadways, its, anatomy; PET shows the traffic along those paths, its biochemistry. This document discusses the principles of PET, the radiopharmaceuticals in PET, PET research, clinical applications of PET, the cost of PET, training of individuals for PET, the role of the United States Department of Energy in PET, and the futures of PET.

  16. Radial reflection diffraction tomography

    DOE Patents [OSTI]

    Lehman, Sean K.

    2012-12-18T23:59:59.000Z

    A wave-based tomographic imaging method and apparatus based upon one or more rotating radially outward oriented transmitting and receiving elements have been developed for non-destructive evaluation. At successive angular locations at a fixed radius, a predetermined transmitting element can launch a primary field and one or more predetermined receiving elements can collect the backscattered field in a "pitch/catch" operation. A Hilbert space inverse wave (HSIW) algorithm can construct images of the received scattered energy waves using operating modes chosen for a particular application. Applications include, improved intravascular imaging, bore hole tomography, and non-destructive evaluation (NDE) of parts having existing access holes.

  17. Stored Luminescence Computed Tomography

    E-Print Network [OSTI]

    Cong, Wenxiang; Wang, Ge

    2013-01-01T23:59:59.000Z

    The phosphor nanoparticles made of doped semiconductors, pre-excited by well-collimated X-ray radiation, were recently reported for their light emission upon NIR light stimulation. The characteristics of X-ray energy storage and NIR stimulated emission is highly desirable to design targeting probes and improve molecular and cellular imaging. Here we propose stored luminescence computed tomography (SLCT), perform realistic numerical simulation, and demonstrate a much-improved spatial resolution in a preclinical research context. The future opportunities are also discussed along this direction.

  18. Medical Imaging Computed Tomography (CT)

    E-Print Network [OSTI]

    Massey, Thomas N.

    Module 10 Medical Imaging · X-rays · Computed Tomography (CT) · Positron Emission Tomography (PET Sources PET-TOF #12;Four Sources PET #12;Four Sources PET-TOF #12;PET Scan MRI CT scan #12;Endocrine Gland,000 pixels! #12;Modern Example of CT Scan with the addition of Surface Shading Standard CT With Surface

  19. Ultrasound-modulated optical tomography 

    E-Print Network [OSTI]

    Nam, Haewon

    2004-09-30T23:59:59.000Z

    Ultrasound-modulated optical tomography is modeled by a linear integral equation and an inverse problem involving a diffusion equation in n spatial dimensions, n=2, 3. Based on measured data, the optical absorption coefficient ?...

  20. Teleseismic transmission and reflection tomography

    E-Print Network [OSTI]

    Burdick, Scott A. (Scott Anthony)

    2014-01-01T23:59:59.000Z

    The aim of seismic tomography is to determine a model of Earth properties that best explain observed seismic data. In practice, the limitations placed on our observations and computational capabilities force us to make a ...

  1. Mathematical Problems of Thermoacoustic Tomography 

    E-Print Network [OSTI]

    Nguyen, Linh V.

    2010-10-12T23:59:59.000Z

    Thermoacoustic tomography (TAT) is a newly emerging modality in biomedical imaging. It combines the good contrast of electromagnetic and good resolution of ultrasound imaging. The mathematical model of TAT is the observability problem for the wave...

  2. EMISSION AND TRANSMISSION NOISE PROPAGATION IN POSITRON EMISSION COMPUTED TOMOGRAPHY

    E-Print Network [OSTI]

    Gullberg, G.T.

    2010-01-01T23:59:59.000Z

    High Resolution Computed Tomography of Positron Emitters,"of Dynamic Emission Computed Tomography," J. Nucl. Med. ~:IN POSITRON EMISSION COMPUTED TOMOGRAPHY RECEIVED lAWRENCE

  3. SINGLE-PHOTON EMISSION COMPUTED TOMOGRAPHY: COMPENSATION FOR CONSTANT ATTENUATION

    E-Print Network [OSTI]

    Gullberg, Grant T.

    2013-01-01T23:59:59.000Z

    in radionuclide computed tomography," IEEE Trans. Nucl.49. M.E.Phelps, Emission computed tomography,~~ Seminars inSINGLE-PHOTON EMISSION COMPUTED TOMOGRAPHY: COMPENSATION FOR

  4. Artifact Simulating Fracture on Cervical Spine Computed Tomography

    E-Print Network [OSTI]

    Shockley, Lee W.; Kendall, John L.

    2011-01-01T23:59:59.000Z

    on Cervical Spine Computed Tomography Lee W. Shockley, MD,patient with computed tomography concerning significant C3-scalp laceration. Computed tomography (CT) of her head was

  5. Thermal Neutron Computed Tomography of Soil Water and Plant Roots

    E-Print Network [OSTI]

    Leanne G. Tumlinson; Hungyuan Liu; Wendy K. Silk; Jan W. Hopmans

    2007-01-01T23:59:59.000Z

    2000. 3D neutron computed tomography: Requirements and2002. Using x-ray computed tomography in hydrology: Systems,of neutron computed tomography in the geosciences. Nucl.

  6. Application of neutron computed tomography in the geosciences

    E-Print Network [OSTI]

    Wilding, M.; Shields, K.; Lesher, C. E.

    2005-01-01T23:59:59.000Z

    of neutron computed tomography in the geosciences Martinthat applies neutron computed tomography (CT) to geologicalthe use of neutron computed tomography (CT) in the analy-

  7. Hyperdense Cerebral Sinus Vein Thrombosis on Computed Tomography

    E-Print Network [OSTI]

    Zeina, Abdel-Rauf; Kassem, Eiass; Klein, Adi; Nachtigal, Alicia

    2010-01-01T23:59:59.000Z

    Vein Thrombosis on Computed Tomography Abdel-Rauf Zeina*1. Unenhanced axial computed tomography (CT) (a-c) shows theBrain unenhanced computed tomography (CT) on admission

  8. Frequency of Incidental Findings on Computed Tomography of Trauma Patients

    E-Print Network [OSTI]

    Devine, Alicia S; Jackson, Corinne S; Lyons, Lisa; Mason, Jon D

    2010-01-01T23:59:59.000Z

    findings on trauma computed tomography scans: experience atfindings in brain computed tomography scans of 3000 headfindings on chest computed tomography angiography performed

  9. Patient Attitudes Regarding Consent for Emergency Department Computed Tomographies

    E-Print Network [OSTI]

    Weigner, Michael B; Basham, Hilary F; Dewar, Kate M; Rupp, Valerie A; Cornelius, Llewellyn; Greenberg, Marna Rayl

    2014-01-01T23:59:59.000Z

    associated with common Computed Tomography examinations andRegarding Consent for Computed Tomographies ucm2007191.htm.for Emergency Department Computed Tomographies Lehigh Valley

  10. advanced computed tomography: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2007-01-01 4 Geometric Tomography: A Limited-View Approach for Computed Tomography Computer Technologies and Information Sciences Websites Summary: Geometric Tomography: A...

  11. Tomography of a laser wakefield accelerator Tomography of a laser wakefield accelerator

    E-Print Network [OSTI]

    history of laser-plasma accelerators is reviewed. The excitation of plasma waves by ultra-short laser Tomography of a laser wakefield accelerator Tomography of a laser wakefield accelerator 692220024 #12; Tomography of a laser wakefield accelerator i #12; Tomography of a laser

  12. Thermoacoustic and Photoacoustic Tomography ... - Purdue University

    E-Print Network [OSTI]

    Plamen Stefanov

    2010-11-09T23:59:59.000Z

    Thermoacoustic and Photoacoustic Tomography with a variable continuous or discontinuous sound speed. Plamen Stefanov. Purdue University. Based on a ...

  13. Mathematics of Thermoacoustic and Photoacoustic Tomography

    E-Print Network [OSTI]

    Kuchment, Peter

    2007-01-01T23:59:59.000Z

    The paper presents a survey of mathematical problems, techniques, and challenges arising in the Thermoacoustic and Photoacoustic Tomography.

  14. Electron tomography of dislocation structures

    SciTech Connect (OSTI)

    Liu, G.S.; House, S.D.; Kacher, J. [Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, 1304 W. Green St., Urbana, IL 61801 (United States); Tanaka, M.; Higashida, K. [Department of Materials Science and Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395 (Japan); Robertson, I.M., E-mail: irobertson@wisc.edu [Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, 1304 W. Green St., Urbana, IL 61801 (United States); Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, WI 53706 (United States)

    2014-01-15T23:59:59.000Z

    Recent developments in the application of electron tomography for characterizing microstructures in crystalline solids are described. The underlying principles for electron tomography are presented in the context of typical challenges in adapting the technique to crystalline systems and in using diffraction contrast imaging conditions. Methods for overcoming the limitations associated with the angular range, the number of acquired images, and uniformity of image contrast are introduced. In addition, a method for incorporating the real space coordinate system into the tomogram is presented. As the approach emphasizes development of experimental solutions to the challenges, the solutions developed and implemented are presented in the form of examples.

  15. Mathematics of thermoacoustic and photoacoustic tomography

    E-Print Network [OSTI]

    Mathematics of thermoacoustic and photoacoustic tomography Peter Kuchment and Leonid Kunyansky in the Thermoacoustic and Photoacoustic To- mography. 1 Introduction Medical tomography has had a huge impact on medical succesfull example of such a combination is the Thermoacoustic Tomography (TAT) (also abbreviated as TCT) [50

  16. PROGRAMME SPECIFICATION Programme name Radiography (Computed Tomography);

    E-Print Network [OSTI]

    Weyde, Tillman

    1 PROGRAMME SPECIFICATION KEY FACTS Programme name Radiography (Computed Tomography); Radiography in a clinical speciality, for example, Computed Tomography, you must successfully complete the Computed-time The postgraduate programmes in Radiography provide advanced education in #12;2 Computed Tomography and Medical

  17. Introduction to Positron Emission Tomography

    E-Print Network [OSTI]

    Oakes, Terry

    range: 1-10 mm Gamma-Ray range: 10 mm - 8 positron annihilation #12;Positron Emission Tomography #12;P.E.T. measures Concentration of Radioactivity 1) Gamma-rays escape from body: External detection possible. 2) Two gamma rays emitted at 180 when a positron annihilates: The annihilation occured somewhere

  18. Self-guided quantum tomography

    E-Print Network [OSTI]

    Christopher Ferrie

    2014-11-10T23:59:59.000Z

    We introduce a self-learning tomographic technique in which the experiment guides itself to an estimate of its own state. Self-guided quantum tomography (SGQT) uses measurements to directly test hypotheses in an iterative algorithm which converges to the true state. We demonstrate through simulation on many qubits that SGQT is a more efficient and robust alternative to the usual paradigm of taking a large amount of informationally complete data and solving the inverse problem of post-processed state estimation.

  19. THERMOACOUSTIC TOMOGRAPHY ARISING IN BRAIN IMAGING ...

    E-Print Network [OSTI]

    2011-02-21T23:59:59.000Z

    In this paper, we study the mathematical model of thermoacoustic and photoacoustic tomography for a sound speed that jumps across a smooth closed surface.

  20. Algorithm for Rapid Tomography of Gas Concentrations

    E-Print Network [OSTI]

    Price, P.N.

    2008-01-01T23:59:59.000Z

    sensing and computed tomography in industrial hygiene.American Industrial Hygiene Association Journal 51: 1165-indoor air. American Industrial Hygiene Association Journal

  1. Metal Artifact Reduction in Computed Tomography /

    E-Print Network [OSTI]

    Karimi, Seemeen

    2014-01-01T23:59:59.000Z

    Monoenergetic imaging of dual-energy CT reduces artifactsartifact reduction by dual energy computed tomography usingimage re- construction for dual energy X-ray transmission

  2. On reconstruction and time reversal in thermoacoustic tomography in acoustically

    E-Print Network [OSTI]

    Kuchment, Peter

    On reconstruction and time reversal in thermoacoustic tomography in acoustically homogeneous of recent approaches to the reconstruction in thermoacoustic/photoacoustic tomography: backprojection of the problem of sound speed recovery is also provided. Keywords: Tomography, thermoacoustic, wave equation. AMS

  3. Two-dimensional ultrasonic computed tomography of growing bones.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Two-dimensional ultrasonic computed tomography of growing bones. P. Lasaygues, E. Franceschini, R: Ultrasonic Computed Tomography, Bone imaging, Born approximation, iterative distorted method I. INTRODUCTION imaging process, using ultrasonic computed tomography. Although this method is known to provide

  4. Computational confocal tomography for simultaneous reconstruction of objects, occlusions,

    E-Print Network [OSTI]

    Fainman, Yeshaiahu

    Computational confocal tomography for simultaneous reconstruction of objects, occlusions computationally intense and novel reconstruction methods that we called "compu- tational confocal tomography." The key to computed tomography is the collection of projections of the data over a range of angles

  5. CLINICAL RESEARCH Clinical Trials Coronary Computed Tomography Angiography

    E-Print Network [OSTI]

    CLINICAL RESEARCH Clinical Trials Coronary Computed Tomography Angiography for Early Triage computed tomography angiography (CTA) in patients with acute chest pain. Background Triage of chest pain disease (CAD), 31% had nonobstructive disease, and 19% had inconclusive or positive computed tomography

  6. Dynamic Computed Tomography, an algebraic reconstruction method with

    E-Print Network [OSTI]

    Promayon, Emmanuel

    Dynamic Computed Tomography, an algebraic reconstruction method with deformation compensation Sofia . . . . . . . . . . . . . . . . . . . . . . . . . . 7 1.2 Computed Tomography . . . . . . . . . . . . . . . . . . . . . . 8 1.3 Dynamic Computed . . . . . . . . . . . . . . . . . . . . . 9 2 Basic tools for Computed Tomography 10 2.1 The Radon Transform

  7. Prevalence of Incidental Findings on Abdominal Computed Tomography Angiograms on Prospective Renal Donors

    E-Print Network [OSTI]

    2015-01-01T23:59:59.000Z

    multidetector computed tomography angiography. Transplantof Radiology CT: computed tomography IF: incidental findings

  8. Utilization of Computed Tomography Angiography in the Evaluation of Acute Pulmonary Embolus

    E-Print Network [OSTI]

    Constantino, Mary; Randall, Geneva; Gosselin, Marc; Vegas, Carl; Brandt, Marissa; Spinning, Kristopher

    2007-01-01T23:59:59.000Z

    providers. Utilization of Computed Tomography Angiography inappropriate use of computed tomography angiography (CTA) in

  9. ADAPTIVE AND ROBUST TECHNIQUES (ART) FOR THERMOACOUSTIC TOMOGRAPHY

    E-Print Network [OSTI]

    Xie, Yao

    ADAPTIVE AND ROBUST TECHNIQUES (ART) FOR THERMOACOUSTIC TOMOGRAPHY By YAO XIE A DISSERTATION.1 Thermoacoustic Tomography . . . . . . . . . . . . . . . . . . . . . 1 1.2 Image Reconstruction Algorithms for TAT

  10. HEAVY-ION RADIOGRAPHY AND HEAVY-ION COMPUTED TOMOGRAPHY

    E-Print Network [OSTI]

    Fabrikant, J.I.

    2010-01-01T23:59:59.000Z

    RADIOGRAPHY AND HEAVY-ION COMPUTED TOMOGRAPHY 1,2 Jacob I .RADIOGRAPHY AND HEAVY-ION COMPUTED TOMOGRAPHY J I Fabrikant,

  11. Using X-Ray Computed Tomography in Pore Structure Characterization...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Using X-Ray Computed Tomography in Pore Structure Characterization for a Berea Sandstone: Resolution Effect. Using X-Ray Computed Tomography in Pore Structure Characterization for...

  12. Thermoacoustic Tomography in Elastic Media

    E-Print Network [OSTI]

    Justin Tittelfitz

    2011-10-11T23:59:59.000Z

    We investigate the problem of recovering the initial displacement f for a solution u of a linear, isotropic, non-homogeneous elastic wave equation, given measurements of u on [0,T] x \\partial \\Omega, where \\Omega\\subset\\R^3 is some bounded domain containing the support of f. For the acoustic wave equation, this problem is known as thermoacoustic tomography (TAT), and has been well-studied; for the elastic wave equation, the situation is somewhat more subtle, and we give sufficient conditions on the Lam\\'e parameters to ensure that recovery is possible.

  13. Fourier Transform Quantum State Tomography

    E-Print Network [OSTI]

    Mohammadreza Mohammadi; Agata M. Branczyk; Daniel F. V. James

    2013-01-17T23:59:59.000Z

    We propose a technique for performing quantum state tomography of photonic polarization-encoded multi-qubit states. Our method uses a single rotating wave plate, a polarizing beam splitter and two photon-counting detectors per photon mode. As the wave plate rotates, the photon counters measure a pseudo-continuous signal which is then Fourier transformed. The density matrix of the state is reconstructed using the relationship between the Fourier coefficients of the signal and the Stokes' parameters that represent the state. The experimental complexity, i.e. different wave plate rotation frequencies, scales linearly with the number of qubits.

  14. Surface Impedance Tomography for Antarctic Sea Ice

    E-Print Network [OSTI]

    Golden, Kenneth M.

    Surface Impedance Tomography for Antarctic Sea Ice C. Sampsona , K. M. Goldena , A. Gullya , A. P, Australia Abstract During the 2007 SIPEX expedition in pack ice off the coast of East Antarctica, we measured the electrical conductivity of sea ice via surface impedance tomography. Resistance data from

  15. Efficiency of quantum state tomography for qubits

    E-Print Network [OSTI]

    Koichi Yamagata

    2011-05-19T23:59:59.000Z

    The efficiency of quantum state tomography is discussed from the point of view of quantum parameter estimation theory, in which the trace of the weighted covariance is to be minimized. It is shown that tomography is optimal only when a special weight is adopted.

  16. REVIEW Open Access Micro computed tomography for

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    REVIEW Open Access Micro computed tomography for vascular exploration Lyubomir Zagorchev1 studies. Micro Computed Tomography (micro-CT) has emerged in recent years as the preferred modality and suggestions aimed at making micro-CT more accurate, replicable, and robust. Introduction Micro Computed

  17. Idiopathic juvenile osteoporosis: a cross-sectional single-centre experience with bone histomorphometry and quantitative computed tomography

    E-Print Network [OSTI]

    Bacchetta, Justine; Wesseling-Perry, Katherine; Gilsanz, Vicente; Gales, Barbara; Pereira, Renata C; Salusky, Isidro B

    2013-01-01T23:59:59.000Z

    and quantitative computed tomography. Pediatric Rheumatologyand quantitative computed tomography Justine Bacchetta 1 ,by quantitative computed tomography (QCT) and their

  18. Roadmap: Radiologic Imaging Sciences -Computed Tomography (with AAS Radiologic Technology) -

    E-Print Network [OSTI]

    Sheridan, Scott

    Roadmap: Radiologic Imaging Sciences - Computed Tomography (with AAS Radiologic Technology 34084 Computed Tomography and Magnetic Resonance Imaging Sectional Anatomy I 2 C RIS 44021 Patient Management in Computed Tomography (CT) 2 C RIS 44025 Computed Tomography (CT) Clinical Education I 3 C

  19. Reconstruction Algorithm for Single Photon Emission Computed Tomography and its

    E-Print Network [OSTI]

    Fokas, A. S.

    Reconstruction Algorithm for Single Photon Emission Computed Tomography and its Numerical Emission Tomography and of Single Photon Emission Computed Tomography are not only two of the most measured by the usual computed tomography. Thus the basic mathematical problem in SPECT is to determine

  20. Positron emission tomography wrist detector

    DOE Patents [OSTI]

    Schlyer, David J. (Bellport, NY); O'Connor, Paul (Bellport, NY); Woody, Craig (Setauket, NY); Junnarkar, Sachin Shrirang (Sound Beach, NY); Radeka, Veljko (Bellport, NY); Vaska, Paul (Sound Beach, NY); Pratte, Jean-Francois (Stony Brook, NY)

    2006-08-15T23:59:59.000Z

    A method of serially transferring annihilation information in a compact positron emission tomography (PET) scanner includes generating a time signal representing a time-of-occurrence of an annihilation event, generating an address signal representing a channel detecting the annihilation event, and generating a channel signal including the time and address signals. The method also includes generating a composite signal including the channel signal and another similarly generated channel signal concerning another annihilation event. An apparatus that serially transfers annihilation information includes a time signal generator, address signal generator, channel signal generator, and composite signal generator. The time signal is asynchronous and the address signal is synchronous to a clock signal. A PET scanner includes a scintillation array, detection array, front-end array, and a serial encoder. The serial encoders include the time signal generator, address signal generator, channel signal generator, and composite signal generator.

  1. State tomography via weak measurements

    E-Print Network [OSTI]

    Shengjun Wu

    2013-02-01T23:59:59.000Z

    Recent work has revealed that the wave function of a pure state can be measured directly and that complementary knowledge of a quantum system can be obtained simultaneously by weak measurements. However, the original scheme applies only to pure states, and it is not efficient because most of the data are discarded by post-selection. Here, we propose tomography schemes for pure states and for mixed states via weak measurements, and our schemes are more efficient because we do not discard any data. Furthermore, we demonstrate that any matrix element of a general state can be directly read from an appropriate weak measurement. The density matrix (with all of its elements) represents all that is directly accessible from a general measurement.

  2. Collimator-free photon tomography

    DOE Patents [OSTI]

    Dilmanian, F. Avraham (Yaphank, NY); Barbour, Randall L. (Westbury, NY)

    1998-10-06T23:59:59.000Z

    A method of uncollimated single photon emission computed tomography includes administering a radioisotope to a patient for producing gamma ray photons from a source inside the patient. Emissivity of the photons is measured externally of the patient with an uncollimated gamma camera at a plurality of measurement positions surrounding the patient for obtaining corresponding energy spectrums thereat. Photon emissivity at the plurality of measurement positions is predicted using an initial prediction of an image of the source. The predicted and measured photon emissivities are compared to obtain differences therebetween. Prediction and comparison is iterated by updating the image prediction until the differences are below a threshold for obtaining a final prediction of the source image.

  3. Collimator-free photon tomography

    DOE Patents [OSTI]

    Dilmanian, F.A.; Barbour, R.L.

    1998-10-06T23:59:59.000Z

    A method of uncollimated single photon emission computed tomography includes administering a radioisotope to a patient for producing gamma ray photons from a source inside the patient. Emissivity of the photons is measured externally of the patient with an uncollimated gamma camera at a plurality of measurement positions surrounding the patient for obtaining corresponding energy spectrums thereat. Photon emissivity at the plurality of measurement positions is predicted using an initial prediction of an image of the source. The predicted and measured photon emissivities are compared to obtain differences therebetween. Prediction and comparison is iterated by updating the image prediction until the differences are below a threshold for obtaining a final prediction of the source image. 6 figs.

  4. Binary Tomography with Deblurring Stefan Weber1

    E-Print Network [OSTI]

    Schnörr, Christoph

    Binary Tomography with Deblurring Stefan Weber1 , Thomas Sch¨ule1,3 , Attila Kuba2 , and Christoph-Verlag Berlin Heidelberg 2006 #12;376 S. Weber et al. quality of the reconstructed images. The correction

  5. ECG-edit function in multidetector-row computed tomography coronary arteriography for patients with arrhythmias.

    E-Print Network [OSTI]

    2008-01-01T23:59:59.000Z

    multi- detector row computed tomography for the evaluationwith multislice computed tomography. J Am Coll Cardiol 2001;multi- detector-row computed tomography: Results in 102

  6. Reduction in downstream test utilization following introduction of coronary computed tomography in a cardiology practice

    E-Print Network [OSTI]

    Karlsberg, Ronald P.; Budoff, Matthew J.; Thomson, Louise E.; Friedman, John D.; Berman, Daniel S.

    2010-01-01T23:59:59.000Z

    introduction of coronary computed tomography in a cardiologyphoton emission computed tomography (SPECT) myocardialÁ Multi-slice computed tomography Á Multi-detector computed

  7. Potentially Low Cost Solution to Extend Use of Early Generation Computed Tomography

    E-Print Network [OSTI]

    Tonna, Joseph E; Balanoff, Amy M; Lewin, Matthew R; Saandari, Namjilmaa; Wintermark, Max

    2010-01-01T23:59:59.000Z

    of Early Generation Computed Tomography Joseph E. Tonna, MD*two- dimensional (2D) computed tomography (CT) images. ThisWhile many modern computed tomography (CT) scanners contain

  8. Sensitivity of Emergency Bedside Ultrasound to Detect Hydronephrosis in Patients with Computed Tomography-proven Stones

    E-Print Network [OSTI]

    2014-01-01T23:59:59.000Z

    DJ, Hall EJ. Computed tomography-an increasing source ofin Patients with Computed Tomography-proven Stones JeffNon-contrast computed tomography (CT) is widely regarded as

  9. Verrucous carcinoma of the foot affecting the bone: Utility of the computed tomography scanner

    E-Print Network [OSTI]

    García-Gavín, J; González-Vilas, D; Rodríguez-Pazos, L; Sánchez-Aguilar, D; Toribio, J

    2010-01-01T23:59:59.000Z

    Frassica FJ, Fishman EK. Computed tomography of the bones ofbone: Utility of the computed tomography scanner J García-of bone invasion. Computed tomography (CT) showed a lytic

  10. Adherence to Head Computed Tomography Guidelines in the Setting of Mild Traumatic Brain Injury

    E-Print Network [OSTI]

    Jones, Landon A; Morley, Eric J; Grant, William D; Wojcik, Susan M; Paolo, William F

    2014-01-01T23:59:59.000Z

    Adherence to Head Computed Tomography Guidelines for Mildal Adherence to Head Computed Tomography Guidelines system,non-contrast head computed tomography (CT) in patients with

  11. Evaluation of a EMCCD detector for emission-transmission computed tomography

    E-Print Network [OSTI]

    Teo, B K; Shestakova, I; Sun, M; Barber, W C; Nagarkar, V V; Hasegawa, B H

    2006-01-01T23:59:59.000Z

    emission-transmission computed-tomography imaging system,”for Emission-Transmission Computed Tomography B. K. Teo, I.sion-transmission computed tomography. The detector has an

  12. Characterization of Biological Effects of Computed Tomography by Assessing the DNA Damage Response

    E-Print Network [OSTI]

    Elgart, Shona Robin

    2014-01-01T23:59:59.000Z

    Brenner DJ, Hall EJ. Computed Tomography - An IncreasingSmith-Bindman R. Is Computed Tomography Safe? New Englandof X-ray Trends: Computed Tomography 2005 – 06 Preliminary

  13. Emergency Department Frequent User: Pilot Study of Intensive Case Management to Reduce Visits and Computed Tomography

    E-Print Network [OSTI]

    Grover, Casey A; Close, Reb JH; Villarreal, Kathy; Goldman, Lee M

    2010-01-01T23:59:59.000Z

    33. Brenner DJ, Hall EJ. Computed tomography – an increasingReduce Visits and Computed Tomography Casey A. Grover* Rebof total images in all computed tomography (CT) scans during

  14. Yield and Clinical Predictors of Thoracic Spine Injury from Chest Computed Tomography for Blunt Trauma

    E-Print Network [OSTI]

    2014-01-01T23:59:59.000Z

    Injury from Chest Computed Tomography for Blunt Trauma Markthe use of chest computed tomography (CT), (CCT) in bluntinjury. 6,7 Chest computed tomography (CCT) evaluation for

  15. Coronary computed tomography angiography predicts subsequent cardiac outcome events: results of the Visipaque CCTA registry study.

    E-Print Network [OSTI]

    Budoff, MJ; Bloom, SA; Chow, BJ; Chandler, AB; Cole, JH

    2015-01-01T23:59:59.000Z

    Event CCTA= Coronary computed tomography angiography; MACE=CONFIRM (COroNary computed tomography angiography evaluationcalcium scoring and computed tomography angiography: current

  16. Statistical Estimation of Quantum Tomography Protocols Quality

    E-Print Network [OSTI]

    Yu. I. Bogdanov; G. Brida; M. Genovese; S. P. Kulik; E. V. Moreva; A. P. Shurupov

    2010-02-18T23:59:59.000Z

    A novel operational method for estimating the efficiency of quantum state tomography protocols is suggested. It is based on a-priori estimation of the quality of an arbitrary protocol by means of universal asymptotic fidelity distribution and condition number, which takes minimal value for better protocol. We prove the adequacy of the method both with numerical modeling and through the experimental realization of several practically important protocols of quantum state tomography.

  17. F]-Fluorodeoxyglucose Positron Emission Tomography and Computed Tomography in Response

    E-Print Network [OSTI]

    Hemminki, Akseli

    , and [18 F]-FDG-uptake was quantitated with small animal PET/CT. Second, we describe a retrospective molecules. Here we investigated the prognostic utility of CT and [18 F]-fluor- odeoxyglucose (FDG) positron[18 F]-Fluorodeoxyglucose Positron Emission Tomography and Computed Tomography in Response

  18. Omni-tomography / Multi-tomography Integrating Multiple Modalities for Simultaneous Imaging

    E-Print Network [OSTI]

    Wang, Ge

    registration and combined acquisition on PET-CT, PET-MRI and other hybrid scanners. There are intrinsic relevant imaging mechanisms such as CT, MRI, PET, SPECT, US, optical, and possibly more. In this paper applications of omni-tomography. Key Words: Tomography, CT, MRI, PET, SPECT, US imaging, optical imaging

  19. Scanning microwave-induced thermoacoustic tomography: Signal, resolution, and contrast

    E-Print Network [OSTI]

    Wang, Lihong

    Scanning microwave-induced thermoacoustic tomography: Signal, resolution, and contrast Geng Ku Scanning thermoacoustic tomography was explored in the microwave region of the electromagnetic spectrum ultrasonic transducer detected the time-resolved thermoacoustic signals. Based on the microwave

  20. Photoacoustic and thermoacoustic tomography: system development for biomedical applications 

    E-Print Network [OSTI]

    Ku, Geng

    2006-04-12T23:59:59.000Z

    Photoacoustic tomography (PAT), as well as thermoacoustic tomography (TAT), utilize electromagnetic radiation in its visible, near infrared, microwave, and radiofrequency forms, respectively, to induce acoustic waves in biological tissues...

  1. Evaluation of Turbine Blades Using Computed Tomography

    E-Print Network [OSTI]

    C. Muralidhar; S. N. Lukose; M. P. Subramanian

    2006-01-01T23:59:59.000Z

    Turbine blades are high value castings having complex internal geometry. Computed Tomography has been employed on Turbine blades for finding out defects and internal details. The wall thickness, rib thickness and radius of curvature are measured from the CT slices. The discontinuities including blockages of cooling passages in the cast material can be detected. 3D visualization of the turbine blade provides in extracting its internal features including inaccessible areas nondestructively, which is not possible through conventional NDE methods. The salient features for evaluation of turbine blades using Tomography are brought out.

  2. Seismic Tomography: Definitions Lapo Boschi (lapo@erdw.ethz.ch)

    E-Print Network [OSTI]

    Boschi, Lapo

    Tomography Seismic tomography is the science of interpreting seismic measurements (seismograms) to derive; that is to say, solve the seismological inverse problem. Seismic data and their interpretation Seismic stationsSeismic Tomography: Definitions Lapo Boschi (lapo@erdw.ethz.ch) September 14, 2009 Seismic

  3. PHOTOACOUSTIC AND THERMOACOUSTIC TOMOGRAPHY WITH AN UNCERTAIN WAVE SPEED

    E-Print Network [OSTI]

    Uhlmann, Gunther

    PHOTOACOUSTIC AND THERMOACOUSTIC TOMOGRAPHY WITH AN UNCERTAIN WAVE SPEED LAURI OKSANEN AND GUNTHER UHLMANN Abstract. We consider the mathematical model of photoacoustic and thermoacoustic tomography. In Thermoacoustic tomography (TAT), see e.g. [8], low frequency microwaves, with wavelengths on the order of 1m

  4. THERMOACOUSTIC TOMOGRAPHY WITH AN ARBITRARY ELLIPTIC OPERATOR MICHAEL V. KLIBANOV

    E-Print Network [OSTI]

    1 THERMOACOUSTIC TOMOGRAPHY WITH AN ARBITRARY ELLIPTIC OPERATOR MICHAEL V. KLIBANOV Abstract. Thermoacoustic tomography is a term for the inverse problem of determining of one of initial conditions. In thermoacoustic tomography (TAT) a short radio frequency pulse is sent in a biological tissue [1, 9]. Some energy

  5. Application of a nudging technique to thermoacoustic tomography

    E-Print Network [OSTI]

    Boyer, Edmond

    Application of a nudging technique to thermoacoustic tomography Xavier Bonnefond and Sébastien Marinesque December 3, 2011 Abstract ThermoAcoustic Tomography (TAT) is a promising, non invasive, medical inversion method. 1 Introduction ThermoAcoustic Tomography (TAT) is a hybrid imaging technique that uses

  6. Review of Parallel Computing Techniques for Computed Tomography Image Reconstruction

    E-Print Network [OSTI]

    Wang, Ge

    Review of Parallel Computing Techniques for Computed Tomography Image Reconstruction Jun Ni1, 3 representative analytic and iterative reconstruction algorithms for X-ray computed tomography (CT), we address X-ray computed tomography (CT) is one of the most important non-invasive medical imaging techniques

  7. Shape Filtering for False Positive Reduction at Computed Tomography Colonography

    E-Print Network [OSTI]

    Whelan, Paul F.

    Shape Filtering for False Positive Reduction at Computed Tomography Colonography Abhilash A) in the automatic detection of colorectal polyps at Computer Aided Detection in Computed Tomography Colonography of the images of the colon obtained using a Computed Tomography (CT) examination of the abdominal region

  8. Edge-Localized Iterative Reconstruction for Computed Tomography

    E-Print Network [OSTI]

    1 Edge-Localized Iterative Reconstruction for Computed Tomography Zhou Yu Student Member, IEEE) can greatly improve the quality of computed tomography (CT) images. In particular, MBR can recover at significantly reduced computational cost. Index Terms--Computed tomography, model based reconstruc- tion

  9. Roadmap: Radiologic Imaging Sciences -Computed Tomography (with AAS Radiologic Technology) -

    E-Print Network [OSTI]

    Sheridan, Scott

    Roadmap: Radiologic Imaging Sciences - Computed Tomography (with AAS Radiologic Technology] Note: Admission to the program is required to enroll in RIS courses RIS 34084 Computed Tomography and Magnetic Resonance Imaging Sectional Anatomy I 2 C RIS 44021 Patient Management in Computed Tomography 2

  10. Edge-Localized Iterative Reconstruction for Computed Tomography

    E-Print Network [OSTI]

    Edge-Localized Iterative Reconstruction for Computed Tomography Zhou Yu Student Member, IEEE, Jean the quality of computed tomography (CT) images. In particular, MBR can recover fine details and small features reduced computational cost. Index Terms--Computed tomography, model based reconstruc- tion, coordinate

  11. Kinetic Model for Motion Compensation in Computed Tomography

    E-Print Network [OSTI]

    1 Kinetic Model for Motion Compensation in Computed Tomography Zhou Yu, Jean-Baptiste Thibault- gorithms have recently been applied to computed tomography and demonstrated superior image quality. MBIR to computed tomography and demonstrated superior image quality performance [1], [2], [3]. These methods

  12. Proton Computed Tomography and Constructing Tracker Boards Gatlin Bredeson

    E-Print Network [OSTI]

    Belanger, David P.

    1 ABSTRACT Proton Computed Tomography and Constructing Tracker Boards By Gatlin Bredeson Scientists tomography (xCT) with proton computed tomography (pCT). During a CT scan, protons pass through a phantom University to build tracker boards to assist in creating a system that seeks to replace X-ray computed

  13. Global transition zone tomography Jeroen Ritsema1

    E-Print Network [OSTI]

    Ritsema, Jeroen

    Global transition zone tomography Jeroen Ritsema1 and Hendrik Jan van Heijst Seismological on accurate models of seismic velocity variation in the upper mantle transition zone (400­1000 km depth. Such data provide new global transition zone constraints. We combined more than a million measurements

  14. Reconstruction in tomography with diffracting sources

    E-Print Network [OSTI]

    Xu, Yuan

    2005-02-17T23:59:59.000Z

    Homogeneous Model . . . . . . . . . . . . . . . . . . . 22 III LIMITED-VIEW THERMOACOUSTIC TOMOGRAPHY1 . . . 24 A. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . 24 1. Analysis of Singularities in Circular Radon Trans- form and Limited-view TAT... . . . . . . . . . . . . . . 26 a. Circular Radon Transform . . . . . . . . . . . . . 26 b. TAT . . . . . . . . . . . . . . . . . . . . . . . . . 27 c. Reconstruction Methods . . . . . . . . . . . . . . 30 2. Numerical Implementation . . . . . . . . . . . . . . . 35 viii CHAPTER...

  15. Single-Shot Quantum Process Tomography

    E-Print Network [OSTI]

    Abhishek Shukla; T. S. Mahesh

    2014-05-27T23:59:59.000Z

    The standard procedure for quantum process tomography (QPT) involves applying the quantum process on a system initialized in each of a complete set of orthonormal states. The corresponding outputs are then characterized by quantum state tomography (QST), which itself requires the measurement of non-commuting observables realized by independent experiments on identically prepared system states. Thus QPT procedure demands a number of independent measurements, and moreover, this number increases rapidly with the size of the system. However, the total number of independent measurements can be greatly reduced with the availability of ancilla qubits. Ancilla assisted process tomography (AAPT) has earlier been shown to require a single QST of system-ancilla space. Ancilla assisted quantum state tomography (AAQST) has also been shown to perform QST in a single measurement. Here we combine AAPT with AAQST to realize a `single-shot QPT' (SSPT), a procedure to characterize a general quantum process in a single collective measurement of a set of commuting observables. We demonstrate experimental SSPT by characterizing several single-qubit processes using a three-qubit NMR quantum register. Furthermore, using the SSPT procedure we experimentally characterize the twirling process and compare the results with theory.

  16. The Relationship between Organ Dose and Patients Size in Multidetector Computed Tomography (MDCT) Scans Utilizing Tube Current Modulation (TCM)

    E-Print Network [OSTI]

    Khatonabadi, Maryam

    2013-01-01T23:59:59.000Z

    Dose Reduction With Chest Computed Tomography Using AdaptiveDose reduction in computed tomography by attenuation-baseddose from cardiac computed tomography before and after

  17. Comments on “Sensitivity of Emergency Bedside Ultrasound to Detect Hydronephrosis in Patients with Computed Tomography-proven Stones”

    E-Print Network [OSTI]

    K?z?lca, Özgür; Oztek, Alp; Senol, Utku

    2014-01-01T23:59:59.000Z

    al. Ultrasonography versus computed tomography for suspectedin Patients with Computed Tomography-proven Stones” Özgürin Patients with Computed Tomography-proven Stones. West J

  18. Usefulness of Computed Tomography Perfusion in Treatment of an Acute Stroke Patient with Unknown Time of Symptom Onset

    E-Print Network [OSTI]

    Fesmire, Francis M; England, Bryan S; Shell, Jared S; Devlin, Thomas G; Buchheit, Ron C

    2014-01-01T23:59:59.000Z

    ischemic stroke using computed tomography perfusion-derivedUsefulness of Computed Tomography Perfusion in Treatment oftime of symptom onset. Computed tomography angiogram (CTA)

  19. Abnormal Arterial Blood Gas and Lactate Levels Do Not Alter Disposition in Adult Blunt Trauma Patients after Early Computed Tomography

    E-Print Network [OSTI]

    Vohra, Taher; Paxton, James

    2013-01-01T23:59:59.000Z

    Patients after Early Computed Tomography Taher Vohra, MDwho also receive computed tomographies (CT) of the chest,cross-sectional computed tomography (CT) of the chest,

  20. Reply to Comments Regarding “Sensitivity of Emergency Bedside Ultrasound to Detect Hydronephrosis in Patients with Computed Tomography-proven Stones”

    E-Print Network [OSTI]

    Riddell, Jeff; Swadron, Stuart

    2014-01-01T23:59:59.000Z

    al. Ultrasonography versus computed tomography for suspectedin Patients with Computed Tomography-proven Stones” Özgürin Patients with Computed Tomography-proven Stones. West J

  1. A Novel Immunofluorescent Computed Tomography (ICT) Method to Localise and Quantify Multiple Antigens in Large Tissue Volumes at High Resolution

    E-Print Network [OSTI]

    2012-01-01T23:59:59.000Z

    Immunofluorescent Computed Tomography Figure 1. IterativeImmunofluorescent Computed Tomography 31. Freund I, DeutschNovel Immunofluorescent Computed Tomography (ICT) Method to

  2. THE ATTENUATED RADON TRANSFORM: APPLICATION TO SINGLE-PHOTON EMISSION COMPUTED TOMOGRAPHY IN THE PRESENCE OF A VARIABLE ATTENUATING MEDIUM

    E-Print Network [OSTI]

    Gullberg, Grant T.

    2013-01-01T23:59:59.000Z

    PHOTON EMISSION COMPUTED TOMOGRAPHY IN THE PRESENCE OF APHOTON EMISSION COMPUTED TOMOGRAPHY IN THE PRESENCE OF APHOTON EMISSION COMPUTED TOMOGRAPHY IN THE PRESENCE OF A

  3. Automated simulation of areal bone mineral density assessment in the distal radius from high-resolution peripheral quantitative computed tomography

    E-Print Network [OSTI]

    Burghardt, A. J.; Kazakia, G. J.; Link, T. M.; Majumdar, S.

    2009-01-01T23:59:59.000Z

    quantitative computed tomography A. J. Burghardt & G. J.2017–2024 Micro-computed tomography has become an importantperipheral quantitative computed tomography (HR-pQCT) is a

  4. The Relationship between Organ Dose and Patients Size in Multidetector Computed Tomography (MDCT) Scans Utilizing Tube Current Modulation (TCM)

    E-Print Network [OSTI]

    Khatonabadi, Maryam

    2013-01-01T23:59:59.000Z

    D. and E. Hall, Computed tomography - An increasing source7430): p. 19. FDA, Computed Tomography (CT). Food and Drugtransmission x-ray computed tomography. Med Phys, 1981. 8(

  5. Process tomography for unitary quantum channels

    SciTech Connect (OSTI)

    Gutoski, Gus [Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2L 2Y5 (Canada)] [Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2L 2Y5 (Canada); Johnston, Nathaniel [Institute for Quantum Computing, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)] [Institute for Quantum Computing, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)

    2014-03-15T23:59:59.000Z

    We study the number of measurements required for quantum process tomography under prior information, such as a promise that the unknown channel is unitary. We introduce the notion of an interactive observable and we show that any unitary channel acting on a d-level quantum system can be uniquely identified among all other channels (unitary or otherwise) with only O(d{sup 2}) interactive observables, as opposed to the O(d{sup 4}) required for tomography of arbitrary channels. This result generalizes to the problem of identifying channels with at most q Kraus operators, and slight improvements can be obtained if we wish to identify such a channel only among unital channels or among other channels with q Kraus operators. These results are proven via explicit construction of large subspaces of Hermitian matrices with various conditions on rank, eigenvalues, and partial trace. Our constructions are built upon various forms of totally nonsingular matrices.

  6. Bachelor of Science, Radiologic Sciences, Computed Tomography Emphasis, 2014-2015 Name ID# Date

    E-Print Network [OSTI]

    Barrash, Warren

    Bachelor of Science, Radiologic Sciences, Computed Tomography Emphasis, 2014-2015 Name ID# Date RADSCI 450 Principles of Computed Tomography RADSCI 450L Principles of Computed Tomography Lab RADSCI 451 Procedural Case Studies in Computed Tomography RADSCI 455 Clinical Experience in Computed Tomography 1 3 1 3

  7. Bachelor of Science, Radiologic Sciences, Computed Tomography Emphasis, 2013-2014 Name ID# Date

    E-Print Network [OSTI]

    Barrash, Warren

    Bachelor of Science, Radiologic Sciences, Computed Tomography Emphasis, 2013-2014 Name ID# Date RADSCI 450 Principles of Computed Tomography RADSCI 450L Principles of Computed Tomography Lab RADSCI 451 Procedural Case Studies in Computed Tomography RADSCI 455 Clinical Experience in Computed Tomography 1 3 1 3

  8. Lung Nodule Detection in Screening Computed Tomography

    E-Print Network [OSTI]

    Gori, I; Cerello, P; Cheran, S C; De Nunzio, G; Fantacci, M E; Kasae, P; Masala, G L; Pérez-Martínez, A; Retico, A

    2007-01-01T23:59:59.000Z

    A computer-aided detection (CAD) system for the identification of pulmonary nodules in low-dose multi-detector helical Computed Tomography (CT) images with 1.25 mm slice thickness is presented. The basic modules of our lung-CAD system, a dot-enhancement filter for nodule candidate selection and a neural classifier for false-positive finding reduction, are described. The results obtained on the collected database of lung CT scans are discussed.

  9. Thermoacoustic tomography arising in brain imaging

    E-Print Network [OSTI]

    Stefanov, Plamen

    2010-01-01T23:59:59.000Z

    We study the mathematical model of thermoacoustic and photoacoustic tomography when the sound speed has a jump across a smooth surface. This models the change of the sound speed in the skull when trying to image the human brain. We derive an explicit inversion formula in the form of a convergent Neumann series under the assumptions that all singularities from the support of the source reach the boundary.

  10. Thermoacoustic tomography arising in brain imaging

    E-Print Network [OSTI]

    Plamen Stefanov; Gunther Uhlmann

    2010-09-09T23:59:59.000Z

    We study the mathematical model of thermoacoustic and photoacoustic tomography when the sound speed has a jump across a smooth surface. This models the change of the sound speed in the skull when trying to image the human brain. We derive an explicit inversion formula in the form of a convergent Neumann series under the assumptions that all singularities from the support of the source reach the boundary.

  11. Thermoacoustic tomography with variable sound speed

    E-Print Network [OSTI]

    Stefanov, Plamen

    2009-01-01T23:59:59.000Z

    We study the mathematical model of thermoacoustic tomography in media with a variable speed for a fixed time interval, greater than the diameter of the domain. In case of measurements on the whole boundary, we give an explicit solution in terms of a Neumann series expansion. We give necessary and sufficient conditions for uniqueness and stability when the measurements are taken on a part of the boundary.

  12. Thermoacoustic tomography with variable sound speed

    E-Print Network [OSTI]

    Plamen Stefanov; Gunther Uhlmann

    2009-05-30T23:59:59.000Z

    We study the mathematical model of thermoacoustic tomography in media with a variable speed for a fixed time interval, greater than the diameter of the domain. In case of measurements on the whole boundary, we give an explicit solution in terms of a Neumann series expansion. We give necessary and sufficient conditions for uniqueness and stability when the measurements are taken on a part of the boundary.

  13. Tomography and spectroscopy as quantum computations

    E-Print Network [OSTI]

    Cesar Miquel; Juan Pablo Paz; Marcos Saraceno; Emmanuel Knill; Raymond Laflamme; Camille Negrevergne

    2001-09-14T23:59:59.000Z

    Determining the state of a system and measuring properties of its evolution are two of the most important tasks a physicist faces. For the first purpose one can use tomography, a method that after subjecting the system to a number of experiments determines all independent elements of the density matrix. For the second task, one can resort to spectroscopy, a set of techniques used to determine the spectrum of eigenvalues of the evolution operator. In this letter, we show that tomography and spectroscopy can be naturally interpreted as dual forms of quantum computation. We show how to adapt the simplest case of the well-known phase estimation quantum algorithm to perform both tasks, giving it a natural interpretation as a simulated scattering experiment. We show how this algorithm can be used to implement an interesting form of tomography by performing a direct measurement of the Wigner function of a quantum system. We present results of such measurements performed on a system of three qubits using liquid state NMR quantum computation techniques in a sample of trichloroethylene. Remarkable analogies with other experiments are discussed.

  14. Constrained optimization in seismic reflection tomography: an SQP ...

    E-Print Network [OSTI]

    2004-07-06T23:59:59.000Z

    Seismic reflection tomography is a method for determining a subsurface velocity model from the traveltimes of seismic waves reflecting on geological interfaces.

  15. Three-Dimensional Thermal Tomography Advances Cancer Treatment...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Three-Dimensional Thermal Tomography Advances Cancer Treatment Technology available for licensing: A 3D technique to detect early skin changes due to radiation treatment in breast...

  16. Minimally invasive diagnostic imaging using high resolution Optical Coherence Tomography

    E-Print Network [OSTI]

    Herz, Paul Richard, 1972-

    2004-01-01T23:59:59.000Z

    Advances in medical imaging have given researchers unprecedented capabilities to visualize, characterize and understand biological systems. Optical Coherence Tomography (OCT) is a high speed, high resolution imaging technique ...

  17. assisted tomography romicat: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    principles behind Doppler tomography, including a comparison of the relative merits of maximum entropy regularisation versus filtered back-projection for implementing the...

  18. abdominal computerized tomography: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    principles behind Doppler tomography, including a comparison of the relative merits of maximum entropy regularisation versus filtered back-projection for implementing the...

  19. A New Numerical Algorithm for Thermoacoustic and Photoacoustic Tomography with Variable Sound Speed

    E-Print Network [OSTI]

    Uhlmann, Gunther

    A New Numerical Algorithm for Thermoacoustic and Photoacoustic Tomography with Variable Sound Speed algorithm for reconstructing an unknown source in Thermoacoustic and Photoacoustic Tomography based Thermoacoustic (TAT) and Photoacoustic (PAT) Tomography are emerging medical imaging modal- ities [32, 30

  20. Reduction of radiation dose to radiosensitive organs and its tradeoff with image quality in Computed Tomography

    E-Print Network [OSTI]

    Zhang, Di

    2012-01-01T23:59:59.000Z

    helical multislice computed tomography examination. MedicalRadiation Dose in X-Ray Computed Tomography. AAPM report NO.of X-ray equipment for computed tomography. (2002). American

  1. Edge Localized Image Sharpening via Reassignment with Application to Computed Tomography

    E-Print Network [OSTI]

    Bhashyam, Srikrishna

    Edge Localized Image Sharpening via Reassignment with Application to Computed Tomography Timothy computed tomography. Practical implementations limit the amount of high frequency content. Keywords: Image enhancement, edge sharpening, computed tomography, wavelets, reassignment 1. INTRODUCTION

  2. Root-canal preparation with FlexMaster: canal shapes analysed by micro-computed tomography

    E-Print Network [OSTI]

    Hubscher, W; Barbakow, F; Peters, O A

    2003-01-01T23:59:59.000Z

    analysed by micro-computed tomography W. Hu bscher 1 , F.shapes analysed by micro-computed tomography. Internationalemploying micro-computed tomography (mCT) at a resolution of

  3. Optimizing Cone Beam Computed Tomography (CBCT) System for Image Guided Radiation Therapy

    E-Print Network [OSTI]

    Park, Chun Joo

    Four-Dimensional Cone-Beam Computed Tomography. Submitted.Four-dimensional cone-beam computed tomography and digitalFlat-panel cone-beam computed tomography for image-guided

  4. FAST MARCHING METHOD TO CORRECT FOR REFRACTION IN ULTRASOUND COMPUTED TOMOGRAPHY

    E-Print Network [OSTI]

    Mueller, Klaus

    FAST MARCHING METHOD TO CORRECT FOR REFRACTION IN ULTRASOUND COMPUTED TOMOGRAPHY Shengying Li Detection Systems ABSTRACT A significant obstacle in the advancement of Ultrasound Computed Tomography has ultrasound breast phantom. 1. INTRODUCTION Ultrasound computed tomography (UCT) has a long history

  5. Non-linear inversion modeling for Ultrasound Computer Tomography: transition from soft to hard tissues imaging

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Non-linear inversion modeling for Ultrasound Computer Tomography: transition from soft to hard Marseille cedex 20, France ABSTRACT Ultrasound Computer Tomography (UCT) is an imaging technique which has experiments. Keyword: Ultrasound Computer Tomography, Inverse Born Approximation, Elliptical Projection

  6. Feasibility and value of fully 3D Monte Carlo reconstruction in Single Photon Emission Computed Tomography

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Emission Computed Tomography (SPECT) images is degraded by physical effects, namely photon attenuation datasets are currently under investigation. Keywords : single photon emission computed tomography; Monte Emission Computed Tomography (SPECT), the qualitative and quantitative accuracy of images is degraded

  7. Contrast Enhanced Computed Tomography can predict the glycosaminoglycan content and biomechanical properties

    E-Print Network [OSTI]

    Contrast Enhanced Computed Tomography can predict the glycosaminoglycan content and biomechanical in this work is to establish the feasibility of using Contrast Enhanced Computed Tomography (CECT peripheral quantitative computed tomography (pQCT), subjected to an unconfined compressive stress relaxation

  8. In-line x-ray phase-contrast tomography and diffraction-contrast tomography study of the ferrite-cementite microstructure in steel

    E-Print Network [OSTI]

    van Vliet, Lucas J.

    In-line x-ray phase-contrast tomography and diffraction-contrast tomography study of the ferrite;In-line X-ray phase-contrast tomography and diffraction-contrast tomography study of the ferrite embedded in a ferrite matrix of medium-carbon steel. The measurements were carried out at the material

  9. 28,183HUSEN ET AL.: TOMOGRAPHY OF SHALLOW SUBDUCTION IN CHILE Local earthquake tomography of shallow subduction in north Chile: A

    E-Print Network [OSTI]

    Boschi, Lapo

    [Graeber and Asch, 1999; C. Haberland and A. Rietbrock, Attenuation tomography in the western central Andes

  10. Comparison of pressure-saturation characteristics derived from computed tomography and lattice Boltzmann simulations

    E-Print Network [OSTI]

    Wildenschild, Dorthe

    Comparison of pressure-saturation characteristics derived from computed tomography and lattice), Comparison of pressure-saturation characteristics derived from computed tomography and lattice Boltzmann

  11. Cryo-electron tomography of bacterial viruses

    SciTech Connect (OSTI)

    Guerrero-Ferreira, Ricardo C. [Division of Pediatric Infectious Diseases, Emory University School of Medicine, Children's Healthcare of Atlanta, Atlanta, GA 30322 (United States)] [Division of Pediatric Infectious Diseases, Emory University School of Medicine, Children's Healthcare of Atlanta, Atlanta, GA 30322 (United States); Wright, Elizabeth R., E-mail: erwrigh@emory.edu [Division of Pediatric Infectious Diseases, Emory University School of Medicine, Children's Healthcare of Atlanta, Atlanta, GA 30322 (United States)

    2013-01-05T23:59:59.000Z

    Bacteriophage particles contain both simple and complex macromolecular assemblages and machines that enable them to regulate the infection process under diverse environmental conditions with a broad range of bacterial hosts. Recent developments in cryo-electron tomography (cryo-ET) make it possible to observe the interactions of bacteriophages with their host cells under native-state conditions at unprecedented resolution and in three-dimensions. This review describes the application of cryo-ET to studies of bacteriophage attachment, genome ejection, assembly and egress. Current topics of investigation and future directions in the field are also discussed.

  12. Characterizing aquifer heterogeneity using hydraulic tomography

    E-Print Network [OSTI]

    Wachter, Brian James

    2008-07-29T23:59:59.000Z

    such as sands and gravels because these materials drain the water so quickly. The K value is highly localized and only represents the portion of the aquifer in which the core was taken. When working with unconsolidated sediments, care must be taken to pack...?????. .?????.1 17 vi LIST OF FIGURES Figure 1: Map of field site and layout of wells used in study (figure modified from Engard, 2006). Figure 2: MOG setup for tomography study. Figure 3: Packed versus unpacked response in an observation well...

  13. Mathematics of Photoacoustic and Thermoacoustic Tomography

    E-Print Network [OSTI]

    Kuchment, Peter

    2009-01-01T23:59:59.000Z

    This is the manuscript of the chapter for a planned Handbook of Mathematical Methods in Imaging that surveys the mathematical models, problems, and algorithms of the Thermoacoustic (TAT) and Photoacoustic (PAT) Tomography. TAT and PAT represent probably the most developed of the several novel ``hybrid'' methods of medical imaging. These new modalities combine different physical types of waves (electromagnetic and acoustic in case of TAT and PAT) in such a way that the resolution and contrast of the resulting method are much higher than those achievable using only acoustic or electromagnetic measurements.

  14. Thermoacoustic tomography with an arbitrary elliptic operator

    E-Print Network [OSTI]

    Michael V. Klibanov

    2012-08-26T23:59:59.000Z

    Thermoacoustic tomography is a term for the inverse problem of determining of one of initial conditions of a hyperbolic equation from boundary measurements. In the past publications both stability estimates and convergent numerical methods for this problem were obtained only under some restrictive conditions imposed on the principal part of the elliptic operator. In this paper logarithmic stability estimates are obatined for an arbitrary variable principal part of that operator. Convergence of the Quasi-Reversibility Method to the exact solution is also established for this case. Both complete and incomplete data collection cases are considered.

  15. Mathematics of Photoacoustic and Thermoacoustic Tomography

    E-Print Network [OSTI]

    Peter Kuchment; Leonid Kunyansky

    2009-12-10T23:59:59.000Z

    This is the manuscript of the chapter for a planned Handbook of Mathematical Methods in Imaging that surveys the mathematical models, problems, and algorithms of the Thermoacoustic (TAT) and Photoacoustic (PAT) Tomography. TAT and PAT represent probably the most developed of the several novel ``hybrid'' methods of medical imaging. These new modalities combine different physical types of waves (electromagnetic and acoustic in case of TAT and PAT) in such a way that the resolution and contrast of the resulting method are much higher than those achievable using only acoustic or electromagnetic measurements.

  16. Momentum computed tomography of charged particles

    E-Print Network [OSTI]

    Yu, Deyang

    2013-01-01T23:59:59.000Z

    The principle of the momentum computed tomography of charged particles is presented. It may be useful for momentum spectroscopy of various beam-matter interactions, especially when very intense beams are involved. It is able to collect the shower of charged particles with the 4Pi solid angle, and suitable for measuring the overall perspective of the arbitrary momentum distribution of the outgoing charged particles induced by arbitrary beams, especially when the other techniques are invalid. The extended collisional region, the strong field approximation and the case without magnetic field are discussed.

  17. Adaptive schemes for incomplete quantum process tomography

    SciTech Connect (OSTI)

    Teo, Yong Siah [Centre for Quantum Technologies, National University of Singapore, Singapore 117543 (Singapore); NUS Graduate School for Integrative Sciences and Engineering, Singapore 117597 (Singapore); Englert, Berthold-Georg [Centre for Quantum Technologies, National University of Singapore, Singapore 117543 (Singapore); Department of Physics, National University of Singapore, Singapore 117542 (Singapore); Rehacek, Jaroslav; Hradil, Zdenek [Department of Optics, Palacky University, 17. listopadu 12, CZ-77146 Olomouc (Czech Republic)

    2011-12-15T23:59:59.000Z

    We propose an iterative algorithm for incomplete quantum process tomography with the help of quantum state estimation. The algorithm, which is based on the combined principles of maximum likelihood and maximum entropy, yields a unique estimator for an unknown quantum process when one has less than a complete set of linearly independent measurement data to specify the quantum process uniquely. We apply this iterative algorithm adaptively in various situations and so optimize the amount of resources required to estimate a quantum process with incomplete data.

  18. Scattered Neutron Tomography Based on A Neutron Transport Inverse Problem

    SciTech Connect (OSTI)

    William Charlton

    2007-07-01T23:59:59.000Z

    Neutron radiography and computed tomography are commonly used techniques to non-destructively examine materials. Tomography refers to the cross-sectional imaging of an object from either transmission or reflection data collected by illuminating the object from many different directions.

  19. Signal processing in scanning thermoacoustic tomography in biological tissues

    E-Print Network [OSTI]

    Wang, Lihong

    Signal processing in scanning thermoacoustic tomography in biological tissues Yuan Xu and Lihong V Microwave-induced thermoacoustic tomography was explored to image biological tissues. Short microwave pulses-induced thermoacoustic waves were detected with a focused ultrasonic transducer to obtain two-dimensional tomographic

  20. Microwave-induced thermoacoustic tomography: Reconstruction by synthetic aperture

    E-Print Network [OSTI]

    Wang, Lihong

    Microwave-induced thermoacoustic tomography: Reconstruction by synthetic aperture Dazi Feng, Yuan thermoacoustic signals, to which the delay-and-sum algorithm was applied for image reconstruc- tion. We greatly-induced thermoacoustic tomography based on focused transducers. Two mi- crowave sources, which had frequencies of 9 and 3

  1. Propagation Beam Consideration for 3D THz Computed Tomography

    E-Print Network [OSTI]

    Boyer, Edmond

    Propagation Beam Consideration for 3D THz Computed Tomography B. Recur, 1, J.P. Guillet, 2 I. Manek, "Refraction losses in terahertz computed tomography," Opt. Commun. 283, 2050­2055 (2010). 8. S. Nadar, H of the beam propagation is developed according to the physical properties of THz waves used in THz computed

  2. High-Resolution Computed Tomography Study of the Cranium of

    E-Print Network [OSTI]

    Allman, John M.

    High-Resolution Computed Tomography Study of the Cranium of a Fossil Anthropoid Primate of these characteristics may have important implications for brain evolution. Here computed tomography is used to examine in the evolutionary development of anthropoids did these characteristics evolve? We recently used X-ray computed

  3. Optimal control techniques for thermo-acoustic tomography Maitine Bergounioux

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    . These hybrid systems use an electromagnetic pulse as an input and record ultrasound waves as an output-acoustic tomography (TAT) when the heating is realized by means of microwaves, and of photo-acoustic tomography (PAT) when optical heating is used. While in TAT waves of radio frequency range are used to trigger

  4. Double-Difference Tomography for Sequestration MVA

    SciTech Connect (OSTI)

    Westman, Erik

    2008-12-31T23:59:59.000Z

    Analysis of synthetic data was performed to determine the most cost-effective tomographic monitoring system for a geologic carbon sequestration injection site. Double-difference tomographic inversion was performed on 125 synthetic data sets: five stages of CO2 plume growth, five seismic event regions, and five geophone arrays. Each resulting velocity model was compared quantitatively to its respective synthetic velocity model to determine an accuracy value. The results were examined to determine a relationship between cost and accuracy in monitoring, verification, and accounting applications using double-difference tomography. The geophone arrays with widely-varying geophone locations, both laterally and vertically, performed best. Additionally, double difference seismic tomography was performed using travel time data from a carbon sequestration site at the Aneth oil field in southeast Utah as part of a Department of Energy initiative on monitoring, verification, and accounting (MVA) of sequestered CO2. A total of 1,211 seismic events were recorded from a borehole array consisting of 22 geophones. Artificial velocity models were created to determine the ease with which different CO2 plume locations and sizes can be detected. Most likely because of the poor geophone arrangement, a low velocity zone in the Desert Creek reservoir can only be detected when regions of test site containing the highest ray path coverage are considered. MVA accuracy and precision may be improved through the use of a receiver array that provides more comprehensive ray path coverage.

  5. 1st World Congress on Industrial Process Tomography, Buxton, Greater Manchester 1417 April 1999. Eddy Current Tomography for Metal

    E-Print Network [OSTI]

    Hua, Yingbo

    . 451 Eddy Current Tomography for Metal Solidification Imaging Minh H. Pham* , Yingbo Hua* , Neil B of molten metal inside a pipe by eddy currents. A complete mathematical model is developed which reveals functions in multiple layered media. Keywords: eddy current tomography, electromagnetic field, numerical

  6. Roadmap: Radiologic Imaging Sciences -Computed Tomography (with certification and ATS Radiologic Technology) -

    E-Print Network [OSTI]

    Sheridan, Scott

    Roadmap: Radiologic Imaging Sciences - Computed Tomography (with certification and ATS Radiologic 34084 Computed Tomography and Magnetic Resonance Imaging Sectional Anatomy I 2 C RIS 44021 Patient Management in Computed Tomography 2 C RIS 44025 Computed Tomography Clinical Education I 3 C RIS 44030

  7. Roadmap: Radiologic Imaging Sciences -Computed Tomography (with certification and ATS Radiologic Technology) -

    E-Print Network [OSTI]

    Sheridan, Scott

    Roadmap: Radiologic Imaging Sciences - Computed Tomography (with certification and ATS Radiologic 34084 Computed Tomography and Magnetic Resonance Imaging Sectional Anatomy I 2 C RIS 44021 Patient Management in Computed Tomography (CT) 2 C RIS 44025 Computed Tomography (CT) Clinical Education I 3 C

  8. Flow Velocity Estimation in Optical Doppler Tomography and A Preliminary Study on Radiation Detection for Hybrid

    E-Print Network [OSTI]

    Piao, Daqing

    Tomography and A Preliminary Study on Radiation Detection for Hybrid Optical Coherence TomographyFlow Velocity Estimation in Optical Doppler Tomography and A Preliminary Study on Radiation Detection for Hybrid Optical Coherence Tomography/Scintigraphy Daqing Piao B.S., Tsinghua University, 1990 M

  9. Compact conscious animal positron emission tomography scanner

    DOE Patents [OSTI]

    Schyler, David J. (Bellport, NY); O'Connor, Paul (Bellport, NY); Woody, Craig (Setauket, NY); Junnarkar, Sachin Shrirang (Sound Beach, NY); Radeka, Veljko (Bellport, NY); Vaska, Paul (Sound Beach, NY); Pratte, Jean-Francois (Stony Brook, NY); Volkow, Nora (Chevy Chase, MD)

    2006-10-24T23:59:59.000Z

    A method of serially transferring annihilation information in a compact positron emission tomography (PET) scanner includes generating a time signal for an event, generating an address signal representing a detecting channel, generating a detector channel signal including the time and address signals, and generating a composite signal including the channel signal and similarly generated signals. The composite signal includes events from detectors in a block and is serially output. An apparatus that serially transfers annihilation information from a block includes time signal generators for detectors in a block and an address and channel signal generator. The PET scanner includes a ring tomograph that mounts onto a portion of an animal, which includes opposing block pairs. Each of the blocks in a block pair includes a scintillator layer, detection array, front-end array, and a serial encoder. The serial encoder includes time signal generators and an address signal and channel signal generator.

  10. Ultra-high resolution computed tomography imaging

    DOE Patents [OSTI]

    Paulus, Michael J. (Knoxville, TN); Sari-Sarraf, Hamed (Knoxville, TN); Tobin, Jr., Kenneth William (Harriman, TN); Gleason, Shaun S. (Knoxville, TN); Thomas, Jr., Clarence E. (Knoxville, TN)

    2002-01-01T23:59:59.000Z

    A method for ultra-high resolution computed tomography imaging, comprising the steps of: focusing a high energy particle beam, for example x-rays or gamma-rays, onto a target object; acquiring a 2-dimensional projection data set representative of the target object; generating a corrected projection data set by applying a deconvolution algorithm, having an experimentally determined a transfer function, to the 2-dimensional data set; storing the corrected projection data set; incrementally rotating the target object through an angle of approximately 180.degree., and after each the incremental rotation, repeating the radiating, acquiring, generating and storing steps; and, after the rotating step, applying a cone-beam algorithm, for example a modified tomographic reconstruction algorithm, to the corrected projection data sets to generate a 3-dimensional image. The size of the spot focus of the beam is reduced to not greater than approximately 1 micron, and even to not greater than approximately 0.5 microns.

  11. Magnified Weak Lensing Cross Correlation Tomography

    SciTech Connect (OSTI)

    Ulmer, Melville P., Clowe, Douglas I.

    2010-11-30T23:59:59.000Z

    This project carried out a weak lensing tomography (WLT) measurement around rich clusters of galaxies. This project used ground based photometric redshift data combined with HST archived cluster images that provide the WLT and cluster mass modeling. The technique has already produced interesting results (Guennou et al, 2010,Astronomy & Astrophysics Vol 523, page 21, and Clowe et al, 2011 to be submitted). Guennou et al have validated that the necessary accuracy can be achieved with photometric redshifts for our purposes. Clowe et al titled "The DAFT/FADA survey. II. Tomographic weak lensing signal from 10 high redshift clusters," have shown that for the **first time** via this purely geometrical technique, which does not assume a standard rod or candle, that a cosmological constant is **required** for flat cosmologies. The intent of this project is not to produce the best constraint on the value of the dark energy equation of state, w. Rather, this project is to carry out a sustained effort of weak lensing tomography that will naturally feed into the near term Dark Energy Survey (DES) and to provide invaluable mass calibration for that project. These results will greatly advance a key cosmological method which will be applied to the top-rated ground-based project in the Astro2020 decadal survey, LSST. Weak lensing tomography is one of the key science drivers behind LSST. CO-I Clowe is on the weak lensing LSST committee, and senior scientist on this project, at FNAL James Annis, plays a leading role in the DES. This project has built on successful proposals to obtain ground-based imaging for the cluster sample. By 1 Jan, it is anticipated the project will have accumulated complete 5-color photometry on 30 (or about 1/3) of the targeted cluster sample (public webpage for the survey is available at http://cencos.oamp.fr/DAFT/ and has a current summary of the observational status of various clusters). In all, the project has now been awarded the equivalent of over 60 nights on 4-m class telescopes, which gives concrete evidence of strong community support for this project. The WLT technique is based on the dependence of the gravitational shear signal on the angular diameter distances between the observer, the lens, and the lensed galaxy to measure cosmological parameters. By taking the ratio of measured shears of galaxies with different redshifts around the same lens, one obtains a measurement of the ratios of the angular diameter distances involved. Making these observations over a large range of lenses and background galaxy redshifts will measure the history of the expansion rate of the universe. Because this is a purely geometric measurement, it is insensitive to any form of evolution of objects or the necessity to understand the physics in the early universe. Thus, WLT was identified by the Dark Energy Task Force as perhaps the best method to measure the evolution of DE. To date, however, the conjecture of the DETF has not been experimentally verified, but will be by the proposed project. The primary reason for the lack of tomography measurements is that one must have an exceptional data-set to attempt the measurement. One needs both extremely good seeing (or space observations) in order to minimize the point spread function smearing corrections on weak lensing shear measurements and deep, multi-color data, from B to z, to measure reliable photometric redshifts of the background galaxies being lensed (which are typically too faint to obtain spectroscopic redshifts). Because the entire process from multi-drizzling the HST images, and then creating shear maps, to gathering the necessary ground based observations, to generating photo-zs and then carrying out the tomography is a complicated task, until the creation of our team, nobody has taken the time to connect all the levels of expertise necessary to carry out this project based on HST archival data. Our data are being used in 2 Ph.D. theses. Kellen Murphy, at Ohio University, is using the tomography data along with simulations in a thesis expected to be completed in Jun

  12. Thermal Neutron Computed Tomography of Soil Water and Plant Roots

    E-Print Network [OSTI]

    Leanne G. Tumlinson; Hungyuan Liu; Wendy K. Silk; Jan W. Hopmans

    2007-01-01T23:59:59.000Z

    images in the McClellan Nuclear Radiation Center tomographyPap. NCT5. McClellan Nuclear Radiation Ctr. , Univ. of1991. McClellan Nuclear Radiation Center safety analysis

  13. Advances in Inverse Transport Methods and Applications to Neutron Tomography

    E-Print Network [OSTI]

    Wu, Zeyun

    2011-02-22T23:59:59.000Z

    and postulated constraints. We illustrate our approach using some neutron-tomography model problems that are several mean-free paths thick and contain highly scattering materials. In these problems we impose reasonable constraints, similar to those...

  14. Scattered neutron tomography based on a neutron transport problem 

    E-Print Network [OSTI]

    Scipolo, Vittorio

    2005-11-01T23:59:59.000Z

    scattering objects because it does not adequately account for the scattering component of the neutron beam intensity exiting the sample. We proposed a new method of computed tomography which employs an inverse problem analysis of both the transmitted...

  15. Properties of Some Integral Transforms Arising in Tomography 

    E-Print Network [OSTI]

    Moon, Sunghwan

    2013-10-11T23:59:59.000Z

    introduce a different Radon-type transform arising in photo acoustic tomography with circular detectors, and study mathematically similar object, a toroidal Radon transform. We also consider the cone transform arising in Compton camera imaging as well...

  16. 3D optical tomography in the presence of void regions

    E-Print Network [OSTI]

    Lorenzo, Jorge Ripoll

    reconstruction scheme for optical tomography based on the equation of radiative transfer," Med. Phys. 26 1698 and F. W¨ubbeling, Mathematical Methods in Image Reconstruction (SIAM, Philadel- phia, 2001). 15. J. Sch

  17. Functional lung imaging in humans using Positron Emission Tomography

    E-Print Network [OSTI]

    Layfield, Dominick, 1971-

    2003-01-01T23:59:59.000Z

    This thesis deals with a method of functional lung imaging using Positron Emission Tomography (PET). In this technique, a radioactive tracer, nitrogen-13, is dissolved in saline solution, and injected into a peripheral ...

  18. Time-dependent seismic tomography and its application to the...

    Open Energy Info (EERE)

    geothermal area, 1996-2006 Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Proceedings: Time-dependent seismic tomography and its application to...

  19. Purely optical tomography : atlas-based reconstruction of brain activation

    E-Print Network [OSTI]

    Custo, Anna

    2008-01-01T23:59:59.000Z

    Diffuse Optical Tomography (DOT) is a relatively new method used to image blood volume and oxygen saturation in vivo. Because of its relatively poor spatial resolution (typically no better than 1-2 cm), DOT is increasingly ...

  20. Anatomical atlas-guided diffuse optical tomography of brain activation

    E-Print Network [OSTI]

    Custo, Anna

    We describe a neuroimaging protocol that utilizes an anatomical atlas of the human head to guide diffuse optical tomography of human brain activation. The protocol is demonstrated by imaging the hemodynamic response to ...

  1. Ultrahigh speed optical coherence tomography for ophthalmic imaging applications

    E-Print Network [OSTI]

    Liu, Jonathan Jaoshin

    2014-01-01T23:59:59.000Z

    Optical coherence tomography (OCT) is a non-contact, non-invasive, micron-scale optical imaging technology that has become a standard clinical tool in ophthalmology. Fourier domain OCT detection methods have enabled higher ...

  2. Embrittlement of RPV steels; An atom probe tomography perspective

    SciTech Connect (OSTI)

    Miller, Michael K [ORNL; Russell, Kaye F [ORNL

    2007-01-01T23:59:59.000Z

    Atom probe tomography has played a key role in the understanding of the embrittlement of neutron irradiated reactor pressure vessel steels through the atomic level characterization of the microstructure. Atom probe tomography has been used to demonstrate the importance of the post weld stress relief treatment in reducing the matrix copper content in high copper alloys, the formation of {approx}-nm-diameter copper-, nickel-, manganese- and silicon-enriched precipitates during neutron irradiation in copper containing RPV steels, and the coarsening of these precipitates during post irradiation heat treatments. Atom probe tomography has been used to detect {approx}2-nm-diameter nickel-, silicon- and manganese-enriched clusters in neutron irradiated low copper and copper free alloys. Atom probe tomography has also been used to quantify solute segregation to, and precipitation on, dislocations and grain boundaries.

  3. Microwave-induced thermoacoustic tomography: reconstruction by synthetic aperture 

    E-Print Network [OSTI]

    Feng, Dazi

    2001-01-01T23:59:59.000Z

    We have applied the synthetic-aperture method to linear-scanning microwave-induced thermoacoustic tomography in biological tissues. A non-focused ultrasonic transducer was used to receive thermoacoustic signals, to which the delay-and-sum algorithm...

  4. Spherical radon transforms and mathematical problems of thermoacoustic tomography 

    E-Print Network [OSTI]

    Ambartsoumian, Gaik

    2009-06-02T23:59:59.000Z

    including approximation theory, integral geometry, inverse problems for PDEs, etc. In Chapter I we give a brief description of thermoacoustic tomography (TAT or TCT) and introduce the SRT. In Chapter II we consider the injectivity problem for SRT. A major...

  5. Iron oxide nanoparticles as a contrast agent for thermoacoustic tomography 

    E-Print Network [OSTI]

    Keho, Aaron Lopez

    2009-06-02T23:59:59.000Z

    An exogenous contrast agent has been developed to enhance the contrast achievable in Thermoacoustic Tomography (TAT). TAT utilizes the penetration depth of microwave energy while producing high resolution images through acoustic waves. A sample...

  6. Development and application of a 4-dimensional Computed Tomography simulator

    E-Print Network [OSTI]

    Chu, Alan

    2007-01-01T23:59:59.000Z

    This thesis presents the development and application of a 4-Dimensional Computed Tomography (4D CT) simulation program. The simulation is used to understand and quantify the sources of image artifacts that arise from ...

  7. Scattered neutron tomography based on a neutron transport problem

    E-Print Network [OSTI]

    Scipolo, Vittorio

    2005-11-01T23:59:59.000Z

    scattering objects because it does not adequately account for the scattering component of the neutron beam intensity exiting the sample. We proposed a new method of computed tomography which employs an inverse problem analysis of both the transmitted...

  8. Revisiting Stopping Rules for Iterative Methods used in Emission Tomography

    E-Print Network [OSTI]

    Renaut, Rosemary

    Stopping Rules for Iterative Methods used in Emission Tomography Hongbin Guo,a, Rosemary A Renautb a Insta.guo@gmail.com (Hongbin Guo) Preprint submitted to Computerized Medical Imaging and Graphics September 28, 2010

  9. aids computed tomography: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Computer-aided diagnosis of rheumatoid arthritis with optical tomography, Part Computer...

  10. Assessment of the relationship between stenosis severity and distribution of coronary artery stenoses on multislice computed tomographic angiography and myocardial ischemia detected by single photon emission computed tomography

    E-Print Network [OSTI]

    2010-01-01T23:59:59.000Z

    photon emission computed tomography Balaji K. Tamarappoo,of 64-slice computed tomography coronary angiography: Aphoton emission computed tomography for the prediction of

  11. Does High Body Mass Index Obviate the Need for Oral Contrast for Abdominal-Pelvic Computed Tomography in Emergency Department Patients?

    E-Print Network [OSTI]

    Harrison, Matthew Lee; Lizotte, Paul E; Holmes, Talmage M; Kenney, Phillip J; Buckner, Charles Barry; Shah, Hemendra R

    2013-01-01T23:59:59.000Z

    1. Brenner DJ, Hall EJ. Computed Tomography. An Increasingis necessary for the computed tomography diagnosis ofto read a computed tomography (CT) of the abdomen and

  12. Optimal phase for coronary interpretations and correlation of ejection fraction using late-diastole and end-diastole imaging in cardiac computed tomography angiography: implications for prospective triggering

    E-Print Network [OSTI]

    2009-01-01T23:59:59.000Z

    of multidetector computed tomography versus echocardiog-diastole imaging in cardiac computed tomography angiography:multi- row detector computed tomography (MDCT) angiog- raphy

  13. Modeling pure methane hydrate dissociation using a numerical simulator from a novel combination of X-ray computed tomography and macroscopic data

    E-Print Network [OSTI]

    Gupta, A.

    2010-01-01T23:59:59.000Z

    Combination of X-ray Computed Tomography and Macroscopicdissociation data. X-ray computed tomography (CT) was usedobtained from x-ray computed tomography analysis combined

  14. Assessment of the relationship between stenosis severity and distribution of coronary artery stenoses on multislice computed tomographic angiography and myocardial ischemia detected by single photon emission computed tomography

    E-Print Network [OSTI]

    2010-01-01T23:59:59.000Z

    of 64-slice computed tomography coronary angiography: Aphoton emission computed tomography for the prediction ofphoton emission computed tomography. Circu- lation 2003;107:

  15. Ultrasonic Tomography for Detecting and Locating Defects in Concrete Structures 

    E-Print Network [OSTI]

    White, Joshua

    2012-07-16T23:59:59.000Z

    acquisition has grown from single-point 3 3 evaluations to automated scanning of larger areas (Streicher et al. 2006; De La Haza et al. n.d.). The tomography system used in this proposed research belongs to this family of phased-array transducers... at ACS working in collaboration with the Federal Institute of Materials Research and Testing in Berlin, Germany (BAM), developed the first ultrasonic tomography system that required no coupling agent (Acoustic Control Systems n.d.). The tomograph, a...

  16. A Detector for Proton Computed Tomography

    SciTech Connect (OSTI)

    Blazey, G.; et al.,

    2013-12-06T23:59:59.000Z

    Radiation therapy is a widely recognized treatment for cancer. Energetic protons have distinct features that set them apart from photons and make them desirable for cancer therapy as well as medical imaging. The clinical interest in heavy ion therapy is due to the fact that ions deposit almost all of their energy in a sharp peak – the Bragg peak- at the very end of their path. Proton beams can be used to precisely localize a tumor and deliver an exact dose to the tumor with small doses to the surrounding tissue. Proton computed tomography (pCT) provides direct information on the location on the target tumor, and avoids position uncertainty caused by treatment planning based on imaging with X-ray CT. The pCT project goal is to measure and reconstruct the proton relative stopping power distribution directly in situ. To ensure the full advantage of cancer treatment with 200 MeV proton beams, pCT must be realized.

  17. Nonlinear regularization techniques for seismic tomography

    SciTech Connect (OSTI)

    Loris, I. [Mathematics Department, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels (Belgium)], E-mail: igloris@vub.ac.be; Douma, H. [Department of Geosciences, Princeton University, Guyot Hall, Washington Road, Princeton, NJ 08544 (United States); Nolet, G. [Geosciences Azur, Universite de Nice-Sophia Antipolis, CNRS/IRD, 250 Rue Albert Einstein, Sophia Antipolis 06560 (France); Daubechies, I. [Program in Applied and Computational Mathematics, Princeton University, Fine Hall, Washington Road, Princeton, NJ 08544 (United States); Regone, C. [BP America Inc., 501 Westlake Park Blvd., Houston, TX 77079 (United States)

    2010-02-01T23:59:59.000Z

    The effects of several nonlinear regularization techniques are discussed in the framework of 3D seismic tomography. Traditional, linear, l{sub 2} penalties are compared to so-called sparsity promoting l{sub 1} and l{sub 0} penalties, and a total variation penalty. Which of these algorithms is judged optimal depends on the specific requirements of the scientific experiment. If the correct reproduction of model amplitudes is important, classical damping towards a smooth model using an l{sub 2} norm works almost as well as minimizing the total variation but is much more efficient. If gradients (edges of anomalies) should be resolved with a minimum of distortion, we prefer l{sub 1} damping of Daubechies-4 wavelet coefficients. It has the additional advantage of yielding a noiseless reconstruction, contrary to simple l{sub 2} minimization ('Tikhonov regularization') which should be avoided. In some of our examples, the l{sub 0} method produced notable artifacts. In addition we show how nonlinear l{sub 1} methods for finding sparse models can be competitive in speed with the widely used l{sub 2} methods, certainly under noisy conditions, so that there is no need to shun l{sub 1} penalizations.

  18. Quantum tomography with wavelet transform in Banach space on Homogeneous space

    E-Print Network [OSTI]

    M. A. Jafarizadeh; M. Mirzaee; M. Rezaee

    2008-01-25T23:59:59.000Z

    The intimate connection between the Banach space wavelet reconstruction method on homogeneous spaces with both singular and nonsingular vacuum vectors, and some of well known quantum tomographies, such as: Moyal-representation for a spin, discrete phase space tomography, tomography of a free particle, Homodyne tomography, phase space tomography and SU(1,1) tomography is explained. Also both the atomic decomposition and banach frame nature of these quantum tomographic examples is explained in details. Finally the connection between the wavelet formalism on Banach space and Q-function is discussed.

  19. State Waste Discharge Permit Application: Electric resistance tomography testing

    SciTech Connect (OSTI)

    Not Available

    1994-04-01T23:59:59.000Z

    This permit application documentation is for a State Waste Discharge Permit issued in accordance with requirements of Washington Administrative Code 173-216. The activity being permitted is a technology test using electrical resistance tomography. The electrical resistance tomography technology was developed at Lawrence Livermore National Laboratory and has been used at other waste sites to track underground contamination plumes. The electrical resistance tomography technology measures soil electrical resistance between two electrodes. If a fluid contaminated with electrolytes is introduced into the soil, the soil resistance is expected to drop. By using an array of measurement electrodes in several boreholes, the areal extent of contamination can be estimated. At the Hanford Site, the purpose of the testing is to determine if the electrical resistance tomography technology can be used in the vicinity of large underground metal tanks without the metal tank interfering with the test. It is anticipated that the electrical resistance tomography technology will provide a method for accurately detecting leaks from the bottom of underground tanks, such as the Hanford Site single-shell tanks.

  20. Abstract--Single-photon emission computed tomography (SPECT) is based on the measurement of radiation emitted by a

    E-Print Network [OSTI]

    Abstract-- Single-photon emission computed tomography (SPECT) is based on the measurement is demonstrated by computer simulation experiments* . I. INTRODUCTION Single-photon emission computed tomography

  1. Finite element analysis and computed tomography based structural rigidity analysis of rat tibia with simulated lytic defects

    E-Print Network [OSTI]

    Vaziri, Ashkan

    Finite element analysis and computed tomography based structural rigidity analysis of rat tibia) (Damron et al., 2003; Mirels, 1989). In contrast, Computed Tomography based Structural Rigidly Ana- lysis

  2. Abstract --Single photon emission computed tomography (SPECT) is based on the measurement of radiation emitted by a

    E-Print Network [OSTI]

    Abstract -- Single photon emission computed tomography (SPECT) is based on the measurement-photon emission computed tomography (SPECT), because of photoelectric absorption and Compton scatter, the gamma

  3. An Efficient Neumann-Series Based Algorithm for Thermoacoustic and Photoacoustic Tomography with Variable Sound Speed

    E-Print Network [OSTI]

    Stefanov, Plamen

    An Efficient Neumann-Series Based Algorithm for Thermoacoustic and Photoacoustic Tomography present an efficient algorithm for reconstructing an unknown source in Thermoacoustic and Photoacoustic of the Neumann-series based algorithm. 1 Introduction Thermoacoustic (TAT) and Photoacoustic (PAT) Tomography

  4. Microwave-induced thermoacoustic tomography: applications and corrections for the effects of acoustic heterogeneities 

    E-Print Network [OSTI]

    Jin, Xing

    2009-05-15T23:59:59.000Z

    This research is primarily focused on developing potential applications for microwaveinduced thermoacoustic tomography and correcting for image degradations caused by acoustic heterogeneities. Microwave-induced thermoacoustic tomography was first...

  5. X-ray Computed Tomography of the Root System of a Live Potted...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    X-ray Computed Tomography of the Root System of a Live Potted Plant X-ray Computed Tomography of the Root System of a Live Potted Plant Being able to see the root structure of a...

  6. SU-E-I-52: Validation of Multi-Frequency Electrical Impedance Tomography Using Computed Tomography

    SciTech Connect (OSTI)

    Kohli, K; Liu, F; Krishnan, K [BC Cancer Agency, Surrey, BC (United Kingdom)

    2014-06-01T23:59:59.000Z

    Purpose: Multi-frequency EIT has been reported to be a potential tool in distinguishing a tissue anomaly from background. In this study, we investigate the feasibility of acquiring functional information by comparing multi-frequency EIT images in reference to the structural information from the CT image through fusion. Methods: EIT data was acquired from a slice of winter melon using sixteen electrodes around the phantom, injecting a current of 0.4mA at 100, 66, 24.8 and 9.9 kHz. Differential EIT images were generated by considering different combinations of pair frequencies, one serving as reference data and the other as test data. The experiment was repeated after creating an anomaly in the form of an off-centered cavity of diameter 4.5 cm inside the melon. All EIT images were reconstructed using Electrical Impedance Tomography and Diffuse Optical Tomography Reconstruction Software (EIDORS) package in 2-D differential imaging mode using one-step Gaussian Newton minimization solver. CT image of the melon was obtained using a Phillips CT Scanner. A segmented binary mask image was generated based on the reference electrode position and the CT image to define the regions of interest. The region selected by the user was fused with the CT image through logical indexing. Results: Differential images based on the reference and test signal frequencies were reconstructed from EIT data. Result illustrated distinct structural inhomogeneity in seeded region compared to fruit flesh. The seeded region was seen as a higherimpedance region if the test frequency was lower than the base frequency in the differential EIT reconstruction. When the test frequency was higher than the base frequency, the signal experienced less electrical impedance in the seeded region during the EIT data acquisition. Conclusion: Frequency-based differential EIT imaging can be explored to provide additional functional information along with structural information from CT for identifying different tissues.

  7. Some Remarks on Quantum Tomography in Laser Cooling

    E-Print Network [OSTI]

    Artur Czerwi?ski

    2015-04-16T23:59:59.000Z

    In this article we take into consideration the evolution model of 3-level quantum systems known as \\textit{laser cooling}. The evolution in this model is given by an equation which is a special case of the general Kossakowski-Lindblad master equation. The explicit knowledge about the evolution makes it possible to apply the stroboscopic tomography to laser cooling. In this article we present some remarks concerning the minimal number of observables and moments of measurement for quantum tomography in laser cooling.

  8. Quantum Process Tomography by 2D Fluorescence Spectroscopy

    E-Print Network [OSTI]

    Leonardo A. Pachon; Andrew H. Marcus; Alan Aspuru-Guzik

    2015-02-09T23:59:59.000Z

    Reconstruction of the dynamics (quantum process tomography) of the single-exciton manifold in energy transfer systems is proposed here on the basis of two-dimensional fluorescence spectroscopy (2D-FS) with phase-modulation. The quantum-process-tomography protocol introduced here benefits from, e.g., the sensitivity enhancement and signal-to-noise ratio ascribed to 2D-FS. Although the isotropically averaged spectroscopic signals depend on the quantum yield parameter $\\Gamma$ of the doubly-excited-exciton manifold, it is shown that the reconstruction of the dynamics is insensitive to this parameter. Applications to foundational and applied problems, as well as further extensions, are discussed.

  9. Quantum Process Tomography by 2D Fluorescence Spectroscopy

    E-Print Network [OSTI]

    Pachon, Leonardo A; Aspuru-Guzik, Alan

    2015-01-01T23:59:59.000Z

    Reconstruction of the dynamics (quantum process tomography) of the single-exciton manifold in energy transfer systems is proposed here on the basis of two-dimensional fluorescence spectroscopy (2D-FS) with phase-modulation. The quantum-process-tomography protocol introduced here benefits from, e.g., the sensitivity enhancement and signal-to-noise ratio ascribed to 2D-FS. Although the isotropically averaged spectroscopic signals depend on the quantum yield parameter $\\Gamma$ of the doubly-excited-exciton manifold, it is shown that the reconstruction of the dynamics is insensitive to this parameter. Applications to foundational and applied problems, as well as further extensions, are discussed.

  10. Bootstrap tomography of high-precision pulses for quantum control

    E-Print Network [OSTI]

    V. V. Dobrovitski; G. de Lange; D. Ristč; R. Hanson

    2010-04-19T23:59:59.000Z

    Long-time dynamical decoupling and quantum control of qubits require high-precision control pulses. Full characterization (quantum tomography) of imperfect pulses presents a bootstrap problem: tomography requires initial states of a qubit which can not be prepared without imperfect pulses. We present a protocol for pulse error analysis, specifically tailored for a wide range of the single solid-state electron spins. Using a single electron spin of a nitrogen-vacancy (NV) center in diamond, we experimentally verify the correctness of the protocol, and demonstrate its usefulness for quantum control tasks.

  11. Multiplexed absorption tomography with calibration-free wavelength modulation spectroscopy

    SciTech Connect (OSTI)

    Cai, Weiwei; Kaminski, Clemens F., E-mail: cfk23@cam.ac.uk [Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge CB2 3RA (United Kingdom)

    2014-04-14T23:59:59.000Z

    We propose a multiplexed absorption tomography technique, which uses calibration-free wavelength modulation spectroscopy with tunable semiconductor lasers for the simultaneous imaging of temperature and species concentration in harsh combustion environments. Compared with the commonly used direct absorption spectroscopy (DAS) counterpart, the present variant enjoys better signal-to-noise ratios and requires no baseline fitting, a particularly desirable feature for high-pressure applications, where adjacent absorption features overlap and interfere severely. We present proof-of-concept numerical demonstrations of the technique using realistic phantom models of harsh combustion environments and prove that the proposed techniques outperform currently available tomography techniques based on DAS.

  12. Quantum Process Tomography via L1-norm Minimization

    E-Print Network [OSTI]

    Robert L. Kosut

    2009-03-05T23:59:59.000Z

    For an initially well designed but imperfect quantum information system, the process matrix is almost sparse in an appropriate basis. Existing theory and associated computational methods (L1-norm minimization) for reconstructing sparse signals establish conditions under which the sparse signal can be perfectly reconstructed from a very limited number of measurements (resources). Although a direct extension to quantum process tomography of the L1-norm minimization theory has not yet emerged, the numerical examples presented here, which apply L1-norm minimization to quantum process tomography, show a significant reduction in resources to achieve a desired estimation accuracy over existing methods.

  13. Radio Science, Volume ???, Number , Pages 131, Radio tomography of the ionosphere: Analysis

    E-Print Network [OSTI]

    Garcia, Raphaël

    Radio Science, Volume ???, Number , Pages 1­31, Radio tomography of the ionosphere: Analysis AND CRESPON: 4D IONOSPHERE TOMOGRAPHY After analysing the forward and inverse problems of radio tomography, the development of Faraday rotation measurements on-board satellites opens the way to magnetospheric radio

  14. Quantitative electron holographic tomography for the 3D characterisation of semiconductor device structures

    E-Print Network [OSTI]

    Dunin-Borkowski, Rafal E.

    Quantitative electron holographic tomography for the 3D characterisation of semiconductor device tomography Silicon devices Device characterisation a b s t r a c t Electron tomography and electron rights reserved. 1. Introduction Dopant profiling of semiconductor devices using off-axis electron

  15. THERMOACOUSTIC TOMOGRAPHY ARISING IN BRAIN IMAGING PLAMEN STEFANOV AND GUNTHER UHLMANN

    E-Print Network [OSTI]

    Uhlmann, Gunther

    THERMOACOUSTIC TOMOGRAPHY ARISING IN BRAIN IMAGING PLAMEN STEFANOV AND GUNTHER UHLMANN Abstract. We study the mathematical model of thermoacoustic and photoacoustic tomography when the sound speed has. Introduction In this paper, we study the mathematical model of thermoacoustic and photoacoustic tomography

  16. Effects of acoustic heterogeneities on transcranial brain imaging with microwave-induced thermoacoustic tomography

    E-Print Network [OSTI]

    Wang, Lihong

    -induced thermoacoustic tomography Xing Jin Department of Biomedical Engineering, Texas A&M University, 3120 TAMU, College: thermoacoustic tomography, transcranial brain imaging, acoustic heterogeneities I. INTRODUCTION Microwave-induced thermoacoustic tomography TAT is a noninvasive and nonionizing imaging modality that can dif- ferentiate

  17. Image distortion in thermoacoustic tomography caused by microwave diffraction Changhui Li,* Manojit Pramanik,

    E-Print Network [OSTI]

    Wang, Lihong

    Image distortion in thermoacoustic tomography caused by microwave diffraction Changhui Li,* Manojit-induced thermoacoustic tomography. The distortion, due to microwave diffraction in the object to be imaged, leads Thermoacoustic TA tomography TAT in biological tis- sue reconstructs the TA source distribution from the acoustic

  18. Reconstructions in limited-view thermoacoustic tomography Yuan Xu and Lihong V. Wanga)

    E-Print Network [OSTI]

    Ambartsoumian, Gaik

    Reconstructions in limited-view thermoacoustic tomography Yuan Xu and Lihong V. Wanga) Optical for publication 9 December 2003; published 11 March 2004 The limited-view problem is studied for thermoacoustic of Physicists in Medicine. DOI: 10.1118/1.1644531 Key words: thermoacoustic tomography, photoacoustic tomography

  19. Tangential resolution improvement in thermoacoustic and photoacoustic tomography using a negative

    E-Print Network [OSTI]

    Wang, Lihong

    Tangential resolution improvement in thermoacoustic and photoacoustic tomography using a negative improve- ment of the tangential resolution in both thermoacoustic and photoa- coustic tomography. In both thermoacoustic and photoacoustic tomography, for a given transducer bandwidth, the aperture size of the detector

  20. THERMOACOUSTIC TOMOGRAPHY WITH VARIABLE SOUND SPEED PLAMEN STEFANOV AND GUNTHER UHLMANN

    E-Print Network [OSTI]

    Uhlmann, Gunther

    THERMOACOUSTIC TOMOGRAPHY WITH VARIABLE SOUND SPEED PLAMEN STEFANOV AND GUNTHER UHLMANN ABSTRACT. We study the mathematical model of thermoacoustic tomography in media with a variable speed are taken on a part of the boundary. 1. INTRODUCTION In thermoacoustic tomography, a short electro

  1. THERMOACOUSTIC TOMOGRAPHY ARISING IN BRAIN IMAGING PLAMEN STEFANOV AND GUNTHER UHLMANN

    E-Print Network [OSTI]

    Stefanov, Plamen

    THERMOACOUSTIC TOMOGRAPHY ARISING IN BRAIN IMAGING PLAMEN STEFANOV AND GUNTHER UHLMANN ABSTRACT. We study the mathematical model of thermoacoustic and photoacoustic tomography when the sound speed has. INTRODUCTION In this paper, we study the mathematical model of thermoacoustic and photoacoustic tomography

  2. Dual-dictionary learning-based iterative image reconstruction for spectral computed tomography application

    E-Print Network [OSTI]

    Wang, Ge

    Dual-dictionary learning-based iterative image reconstruction for spectral computed tomography-based iterative image reconstruction for spectral computed tomography application Bo Zhao1 , Huanjun Ding1 , Yang discriminating photon-counting detectors, such as cadmium­zinc­telluride (CZT), in spectral computed tomography

  3. May 1, 2003 / Vol. 28, No. 9 / OPTICS LETTERS 701 Projected index computed tomography

    E-Print Network [OSTI]

    Bhargava, Rohit

    May 1, 2003 / Vol. 28, No. 9 / OPTICS LETTERS 701 Projected index computed tomography Adam M. Zysk Projected index computed tomography (PICT) is a new imaging technique that provides a computed recon structure is evident. Recently the tools of computed tomography were applied to optical microscopy

  4. Adaptive Noise Reduction toward Low-dose Computed Tomography Hongbing Lu*ad

    E-Print Network [OSTI]

    Adaptive Noise Reduction toward Low-dose Computed Tomography Hongbing Lu*ad , Xiang Lia , Lihong phantom projections acquired by a GE spiral computed tomography (CT) scanner under 10 mAs tube current, computed tomography, adaptive filtering, edge- preserving smoothing, streak artifacts. 1. INTRODUCTION

  5. Experimental measurement of human head motion for high-resolution computed tomography

    E-Print Network [OSTI]

    Wang, Ge

    Experimental measurement of human head motion for high-resolution computed tomography system design experimentally measured for high-resolution computed tomography CT design using a Canon digital camera. Our goal-Optical Instrumentation Engineers. DOI: 10.1117/1.3454379 Subject terms: head motion; computed tomography CT ; image

  6. Adaptive Bolus Chasing Computed Tomography Angiography: Control Scheme and Experimental Results

    E-Print Network [OSTI]

    Wang, Ge

    Adaptive Bolus Chasing Computed Tomography Angiography: Control Scheme and Experimental Results to synchronize the bolus peak in a patient's vascular system and the imaging aperture of a computed tomography standard. Keywords Adaptive bolus chasing; Computed Tomography Angiography I. Introduction With the advent

  7. Using X-ray computed tomography in pore structure characterization for a Berea sandstone: Resolution effect

    E-Print Network [OSTI]

    Hu, Qinhong "Max"

    Using X-ray computed tomography in pore structure characterization for a Berea sandstone Keywords: XCT Pore structure characterization Resolution effect MIP s u m m a r y X-ray computed tomography electron microscopy (Ioannidis et al., 1996), X-ray computed tomography (XCT) with either conventional

  8. Bachelor of Science, Radiologic Sciences, Computed Tomography Emphasis, 2012-2013 Name ID# Date

    E-Print Network [OSTI]

    Barrash, Warren

    Bachelor of Science, Radiologic Sciences, Computed Tomography Emphasis, 2012-2013 Name ID# Date Imaging 3 RADSCI 431 CT Radiation Dose and Risk Analysis 1 RADSCI 450 Principles of Computed Tomography 3 RADSCI 450L Principles of Computed Tomography Lab 1 RADSCI 451 Procedural Case Studies in Computed

  9. Reconstruction for proton computed tomography by tracing proton trajectories: A Monte Carlo study

    E-Print Network [OSTI]

    Reconstruction for proton computed tomography by tracing proton trajectories: A Monte Carlo study 11 January 2006; published 22 February 2006 Proton computed tomography pCT has been explored computed tomography pCT has several potential ad- vantages in medical applications. Its favorable dose

  10. An Exact Modeling of Signal Statistics in Energy-integrating X-ray Computed Tomography

    E-Print Network [OSTI]

    An Exact Modeling of Signal Statistics in Energy-integrating X-ray Computed Tomography Yi Fan1 used by modern computed tomography (CT) scanners and has been an interesting research topic 1. INTRODUCTION In x-ray computed tomography (CT), Poisson noise model has been widely used in noise

  11. 18. Ultrasonic Computed Tomography Philippe Lasaygues, Rgine Guillermin, Jean-Pierre Lefebvre

    E-Print Network [OSTI]

    Boyer, Edmond

    18. Ultrasonic Computed Tomography Philippe Lasaygues, Régine Guillermin, Jean-Pierre Lefebvre ­ France Abstract: Ultrasonic Computed Tomography (UCT) is a full digital imaging technique, which consists, or the acoustical impedance of the medium. Ultrasonic Computed Tomography (UCT), which combines X-ray Computed

  12. On the data dependent filtration techniques in the single-photon emission computed tomography

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    On the data dependent filtration techniques in the single-photon emission computed tomography J computed tomography (SPECT) data modeled as the 2D attenuated ray transform with Poisson noise.G.Novikov, A noise property analysis of single-photon emission computed tomography data, Inverse Problems 20, pp.175

  13. Fast three-dimensional terahertz computed tomography using real-time line projection of

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Fast three-dimensional terahertz computed tomography using real-time line projection of intense terahertz computed tomography by using real-time line projection of intense terahertz beam generated). 4. B. Ferguson, S. Wang, D. Gray, D. Abbot, and X.-C. Zhang, "T-ray computed tomography," Opt. Lett

  14. Neutron Stimulated Emission Computed Tomography of Stable Isotopes

    E-Print Network [OSTI]

    on the development of a new molecular imaging technique using inelastic scattering of fast neutrons. Earlier studies characteristic gamma photons through inelastic scattering of an external neutron beam. These stable isotopes canNeutron Stimulated Emission Computed Tomography of Stable Isotopes Carey E. Floyd Jr.*ab , Calvin

  15. Calibration Using Matrix Completion with Application to Ultrasound Tomography

    E-Print Network [OSTI]

    Vetterli, Martin

    1 Calibration Using Matrix Completion with Application to Ultrasound Tomography Reza Parhizkar, IEEE Abstract--We study the application of matrix completion in the process of calibrating physical devices. In particular we propose an algorithm together with reconstruction bounds for calibrating

  16. Adaptive optics enhanced simultaneous en-face optical coherence tomography

    E-Print Network [OSTI]

    Dainty, Chris

    Adaptive optics enhanced simultaneous en-face optical coherence tomography and scanning laser ophthalmoscopy David Merino and Chris Dainty Applied Optics Group, Department of Experimental Physics, National and Adrian Gh. Podoleanu Applied Optics Group, School of Physical Sciences, University of Kent at Canterbury

  17. Electrical Impedance Tomography in geophysics, application of EIDORS

    E-Print Network [OSTI]

    Adler, Andy

    Electrical Impedance Tomography in geophysics, application of EIDORS Lesparre N., Adler A., Gibert to adapt EIDORS for applications in geophysics. In geophysics, we apply EIT in order to image inner. The spatial resolution of the method in geophysics is of the order of meters and the penetration depth can

  18. Variationally Constrained Numerical Solution of Electrical Impedance Tomography

    E-Print Network [OSTI]

    Zhang, Yin

    deposits [77], detection of leaks in underground storage tanks [79] and for monitoring flows of injected the influence of external electric fields [58]. Let us consider a bounded, simply connected set# # IR d , for d the electric field and the electric current at location x # # Electrical Impedance Tomography (EIT

  19. Volumetric Reconstruction in the MicroCAT Tomography System

    E-Print Network [OSTI]

    Cates, Josh

    0, half of the volume depth. . . . 59 vi #12; List of Figures 1.1 Scanning geometry of the MicroCAT system. . . . . . . . . . . . . . . . 6 1.2 Top view of MicroCAT scanning geometry, showing the pathVolumetric Reconstruction in the MicroCAT Tomography System A Thesis Presented for the Master

  20. Ultrasound-modulated optical tomography in soft biological tissues

    E-Print Network [OSTI]

    Sakadzic, Sava

    2007-09-17T23:59:59.000Z

    Ultrasound-modulated Optical Tomography in Soft Biological Tissues. (May 2006) Sava Sakad•zi¶c, B.S., University of Belgrade, Serbia and Montenegro; M.S., University of Belgrade, Serbia and Montenegro Chair of Advisory Committee: Dr. Lihong V. Wang Optical...

  1. Spherical radon transforms and mathematical problems of thermoacoustic tomography

    E-Print Network [OSTI]

    Ambartsoumian, Gaik

    2009-06-02T23:59:59.000Z

    The spherical Radon transform (SRT) integrates a function over the set of all spheres with a given set of centers. Such transforms play an important role in some newly developing types of tomography as well as in several areas of mathematics...

  2. Optical Coherence Tomography for Neurosurgical Imaging of Human Intracortical Melanoma

    E-Print Network [OSTI]

    Boppart, Stephen

    Optical Coherence Tomography for Neurosurgical Imaging of Human Intracortical Melanoma Stephen A an intracortical melanoma. INSTRUMENTATION: OCT is a new, noncontact, high-speed imaging technology capable for imaging within the surgical field. Cadaveric human cortex with metastatic melanoma was harvested

  3. USING OPTICAL COHERENCE TOMOGRAPHY TO EXAMINE THE SUBSURFACE MORPHOLOGY OF

    E-Print Network [OSTI]

    Barton, Jennifer K.

    : (1) a homogeneous glassy phase; (2) a liquid­liquid phase separated state; and (3) a crystallizedUSING OPTICAL COHERENCE TOMOGRAPHY TO EXAMINE THE SUBSURFACE MORPHOLOGY OF CHINESE GLAZES M of their glazes. The images revealed unique phase assemblage modes in different samples. The results suggest

  4. rf testbed for thermoacoustic tomography D. Fallon,1

    E-Print Network [OSTI]

    Hanson, George

    rf testbed for thermoacoustic tomography D. Fallon,1 L. Yan,2 G. W. Hanson,3 and S. K. Patch4,a 1 Received 28 October 2008; accepted 22 April 2009; published online 9 June 2009 Thermoacoustic signal is a preferred acoustic coupling medium for thermoacoustics because acoustic and electromagnetic waves propagate

  5. Time reversal in thermoacoustic tomography - an error estimate

    E-Print Network [OSTI]

    Hristova, Yulia

    2008-01-01T23:59:59.000Z

    The time reversal method in thermoacoustic tomography is used for approximating the initial pressure inside a biological object using measurements of the pressure wave made outside the object. This article presents error estimates for the time reversal method in the cases of variable, non-trapping sound speeds.

  6. A family of inversion formulas in Thermoacoustic Tomography

    E-Print Network [OSTI]

    Nguyen, Linh V

    2009-01-01T23:59:59.000Z

    We present a family of closed form inversion formulas in thermoacoustic tomography in the case of a constant sound speed. The formulas are presented in both time-domain and frequency-domain versions. As special cases, they imply most of the previously known filtered backprojection type formulas.

  7. On singularities and instability of reconstruction in thermoacoustic tomography

    E-Print Network [OSTI]

    Nguyen, Linh V

    2009-01-01T23:59:59.000Z

    We consider the problem of thermoacoustic tomography (TAT), in which one needs to reconstruct the initial value of a solution of the wave equation from its value on an observation surface. We show that if some geometric rays for the equation do not intersect the observation surface, the reconstruction in TAT is not H\\"{o}lder stable.

  8. Asymmetries in Electrical Impedance Tomography Lung Images Bartlomiej Grychtol1

    E-Print Network [OSTI]

    Adler, Andy

    Asymmetries in Electrical Impedance Tomography Lung Images Bartlomiej Grychtol1 and Andy Adler2 1, it has been used to image the thorax, to monitor the movement of blood and gas in the heart and lungs. One key application of EIT is to determine the distribution of ventilation within the lungs

  9. absorption spectroscopic tomography: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    absorption spectroscopic tomography First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Separation of...

  10. Insights into the structure of the upper mantle beneath the Murray Basin from 3D teleseismic tomography

    E-Print Network [OSTI]

    Rawlinson, Nick

    tomography studies have been carried out in western Victoria (Graeber et al. 2002) and northern Tasmania

  11. Robust statistical reconstruction for charged particle tomography

    DOE Patents [OSTI]

    2013-10-08T23:59:59.000Z

    Systems and methods for charged particle detection including statistical reconstruction of object volume scattering density profiles from charged particle tomographic data to determine the probability distribution of charged particle scattering using a statistical multiple scattering model and determine a substantially maximum likelihood estimate of object volume scattering density using expectation maximization (ML/EM) algorithm to reconstruct the object volume scattering density. The presence of and/or type of object occupying the volume of interest can be identified from the reconstructed volume scattering density profile. The charged particle tomographic data can be cosmic ray muon tomographic data from a muon tracker for scanning packages, containers, vehicles or cargo. The method can be implemented using a computer program which is executable on a computer.

  12. Individual patient data meta-analysis for the clinical assessment of coronary computed tomography angiography: protocol of the Collaborative Meta-Analysis of Cardiac CT (CoMe-CCT)

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    Feyter PJ: 64-slice computed tomography coronary angiographyof 64-slice computed tomography coronary angiography inmultislice spiral computed tomography: impact of heart rate.

  13. Low fingertip temperature rebound measured by digital thermal monitoring strongly correlates with the presence and extent of coronary artery disease diagnosed by 64-slice multi-detector computed tomography

    E-Print Network [OSTI]

    2009-01-01T23:59:59.000Z

    64-slice multi-detector computed tomography Naser Ahmadi ĆÁ Framingham risk score Á Computed tomography angiography Áultra- sound, computed tomography, magnetic resonance

  14. Using electrical impedance tomography to map subsurface hydraulic conductivity

    DOE Patents [OSTI]

    Berryman, James G. (Danville, CA); Daily, William D. (Livermore, CA); Ramirez, Abelardo L. (Pleasanton, CA); Roberts, Jeffery J. (Livermore, CA)

    2000-01-01T23:59:59.000Z

    The use of Electrical Impedance Tomography (EIT) to map subsurface hydraulic conductivity. EIT can be used to map hydraulic conductivity in the subsurface where measurements of both amplitude and phase are made. Hydraulic conductivity depends on at least two parameters: porosity and a length scale parameter. Electrical Resistance Tomography (ERT) measures and maps electrical conductivity (which can be related to porosity) in three dimensions. By introducing phase measurements along with amplitude, the desired additional measurement of a pertinent length scale can be achieved. Hydraulic conductivity controls the ability to flush unwanted fluid contaminants from the surface. Thus inexpensive maps of hydraulic conductivity would improve planning strategies for subsequent remediation efforts. Fluid permeability is also of importance for oil field exploitation and thus detailed knowledge of fluid permeability distribution in three-dimension (3-D) would be a great boon to petroleum reservoir analysts.

  15. Quantum tomography meets dynamical systems and bifurcations theory

    SciTech Connect (OSTI)

    Goyeneche, D., E-mail: dardo.goyeneche@cefop.udec.cl [Departamento de Fisíca, Universidad de Concepción, Casilla 160-C, Concepción, Chile and Center for Optics and Photonics, Universidad de Concepción, Casilla 4012, Concepción (Chile); Torre, A. C. de la [Departamento de Física, Universidad Nacional de Mar del Plata, IFIMAR-CONICET, Dean Funes 3350, 7600 Mar del Plata (Argentina)

    2014-06-15T23:59:59.000Z

    A powerful tool for studying geometrical problems in Hilbert spaces is developed. We demonstrate the convergence and robustness of our method in every dimension by considering dynamical systems theory. This method provides numerical solutions to hard problems involving many coupled nonlinear equations in low and high dimensions (e.g., quantum tomography problem, existence and classification of Pauli partners, mutually unbiased bases, complex Hadamard matrices, equiangular tight frames, etc.). Additionally, this tool can be used to find analytical solutions and also to implicitly prove the existence of solutions. Here, we develop the theory for the quantum pure state tomography problem in finite dimensions but this approach is straightforwardly extended to the rest of the problems. We prove that solutions are always attractive fixed points of a nonlinear operator explicitly given. As an application, we show that the statistics collected from three random orthonormal bases is enough to reconstruct pure states from experimental (noisy) data in every dimension d ? 32.

  16. Practical variational tomography for critical 1D systems

    E-Print Network [OSTI]

    Jong Yeon Lee; Olivier Landon-Cardinal

    2014-12-01T23:59:59.000Z

    We improve upon a recently introduced efficient quantum state reconstruction procedure targeted to states well-approximated by the multi-scale entanglement renormalization ansatz (MERA), e.g., ground states of critical models. We show how to numerically select a subset of experimentally accessible measurements which maximizes information extraction about renormalized particles, thus dramatically reducing the required number of physical measurements. We numerically estimate the number of measurements required to characterize the ground state of the critical 1D Ising (resp. XX) model and find that MERA tomography on 16-qubit (resp. 24-qubit) systems requires the same experimental effort than brute-force tomography on 8 qubits. We derive a bound computable from experimental data which certifies the distance between the experimental and reconstructed states.

  17. Systematic errors in current quantum state tomography tools

    E-Print Network [OSTI]

    Christian Schwemmer; Lukas Knips; Daniel Richart; Tobias Moroder; Matthias Kleinmann; Otfried Gühne; Harald Weinfurter

    2014-07-22T23:59:59.000Z

    Common tools for obtaining physical density matrices in experimental quantum state tomography are shown here to cause systematic errors. For example, using maximum likelihood or least squares optimization for state reconstruction, we observe a systematic underestimation of the fidelity and an overestimation of entanglement. A solution for this problem can be achieved by a linear evaluation of the data yielding reliable and computational simple bounds including error bars.

  18. Photoacoustic computed tomography in biological tissues: algorithms and breast imaging

    E-Print Network [OSTI]

    Xu, Minghua

    2004-11-15T23:59:59.000Z

    are investigated in Chapter III and IV, respectively. Finally, a prototype of an RF-induced PA imaging system is introduced and experiments using phantom samples as well as a preliminary study of breast imaging for cancer detection are reported in Chapter V... PHOTOACOUSTIC COMPUTED TOMOGRAPHY IN BIOLOGICAL TISSUES: ALGORITHMS AND BREAST IMAGING A Dissertation by MINGHUA XU Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements...

  19. Coral Extension Rate Analysis Using Computed Axial Tomography

    E-Print Network [OSTI]

    Yudelman, Eleanor Ann

    2014-01-10T23:59:59.000Z

    CORAL EXTENSION RATE ANALYSIS USING COMPUTED AXIAL TOMOGRAPHY A Thesis by ELEANOR ANN YUDELMAN Submitted to the Office of Graduate and Professional Studies of Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE Chair of Committee, Niall Slowey Committee Members, Deborah Thomas Benjamin Giese George P. Schmahl Head of Department, Deborah Thomas May 2014 Major Subject: Oceanography Copyright 2014 Eleanor Ann Yudelman ii ABSTRACT...

  20. ?A cylindrical specimen holder for electron cryo-tomography

    E-Print Network [OSTI]

    Palmer, Colin Michael

    2013-03-12T23:59:59.000Z

    . . . . . . . . . . . . . . . . . . . . . . . . . 57 3.6 Characterisation of carbon nanopipettes . . . . . . . . . . . . . . . . 59 3.7 Discussion of the manufacturing process . . . . . . . . . . . . . . . . 63 4 Cryo-tomography 67 4.1 Specimen preparation I... . . . . . . . . . . . . . . . . . 60 3.7 Elemental maps and longitudinal EDX linescan of a carbon nanopipette 61 3.8 Transverse EDX linescan of a carbon nanopipette . . . . . . . . . . . 62 4.1 Transmission electron micrograph of a blocked carbon nanopipette tip 68 4.2 A carbon...

  1. Recent developments in guided wave travel time tomography

    SciTech Connect (OSTI)

    Zon, Tim van; Volker, Arno [TNO, Stieltjesweg 1, P.O. box 155 2600 AD Delft (Netherlands)

    2014-02-18T23:59:59.000Z

    The concept of predictive maintenance using permanent sensors that monitor the integrity of an installation is an interesting addition to the current method of periodic inspections. Guided wave tomography had been developed to create a map of the wall thickness using the travel times of guided waves. It can be used for both monitoring and for inspection of pipe-segments that are difficult to access, for instance at the location of pipe-supports. An important outcome of the tomography is the minimum remaining wall thickness, as this is critical in the scheduling of a replacement of the pipe-segment. In order to improve the sizing accuracy we have improved the tomography scheme. A number of major improvements have been realized allowing to extend the application envelope to pipes with a larger wall thickness and to larger distances between the transducer rings. Simulation results indicate that the sizing accuracy has improved and that is now possible to have a spacing of 8 meter between the source-ring and the receiver-ring. Additionally a reduction of the number of sensors required might be possible as well.

  2. Preprocessing of backprojection images in the McClellan Nuclear Radiation Center tomography system

    E-Print Network [OSTI]

    Gibbons, Matthew R.; Shields, Kevin

    1998-01-01T23:59:59.000Z

    Images in the McClellan Nuclear Radiation Center TomographyBays,” McClellan Nuclear Radiation Center report MNRC-0057-

  3. Software-defined Radio Based Wireless Tomography: Experimental Demonstration and Verification

    SciTech Connect (OSTI)

    Bonior, Jason D [ORNL; Hu, Zhen [Tennessee Technological University; Guo, Terry N. [Tennessee Technological University; Qiu, Robert C. [Tennessee Technological University; Browning, James P. [United States Air Force Research Laboratory, Wright-Patterson Air Force Base; Wicks, Michael C. [University of Dayton Research Institute

    2015-01-01T23:59:59.000Z

    This letter presents an experimental demonstration of software-defined-radio-based wireless tomography using computer-hosted radio devices called Universal Software Radio Peripheral (USRP). This experimental brief follows our vision and previous theoretical study of wireless tomography that combines wireless communication and RF tomography to provide a novel approach to remote sensing. Automatic data acquisition is performed inside an RF anechoic chamber. Semidefinite relaxation is used for phase retrieval, and the Born iterative method is utilized for imaging the target. Experimental results are presented, validating our vision of wireless tomography.

  4. A rapid method for converting medical Computed Tomography scanner topogram attenuation scale to Hounsfield Unit scale and to obtain relative density values

    E-Print Network [OSTI]

    Long, Bernard

    A rapid method for converting medical Computed Tomography scanner topogram attenuation scale online 17 July 2008 Keywords: Computed Tomography Attenuation Density calibration Minerals Medical Computed Tomography scanners permit to rapidly obtain qualitative and quantitative information on objects

  5. The Vector representation of the Standard Quantum Process Tomography

    E-Print Network [OSTI]

    Wu Xiaohua

    2012-12-01T23:59:59.000Z

    The characterization of the evolution of a quantum system is one of the main tasks to accomplish to achieve quantum information processing. The standard quantum process tomography (SQPT) has the unique property that it can be applied without introducing any additional quantum resources. In present work, we shall focus on the following two topics about the SQPT. At first, in the SQPT protocol for a $d$-dimensional system, one should encounter a problem in solving of a set of $d^4$ linear equations in order to get the matrix containing the complete information about the unknown quantum channel. Until now, the general form of the solution is unknown. And a long existed conviction is that the solutions are not unique. Here, we shall develop a self-consistent scheme, in which bounded linear operators are presented by vectors, to construct the set of linear equations. With the famous Cramer's rule for the set of linear equations, we are able to give the general form of the solution and prove that it is unique. In second, the central idea of the SQPT is to prepare a set of linearly independent inputs and measuring the outputs via the quantum state tomography (QST). Letting the inputs and the measurements be prepared by two sets of the rank-one positive-operator-valued measures [POVMs], where each POVM is supposed to be linearly independent and informationally complete (IC), we observe that SQPT now is equivalent to deciding a unknown state with a set of product IC-POVM in the $d^2$-dimensional Hilbert space. Following the general linear state tomography theory, we show that the product symmetric IC-POVM should minimize the mean-square Hilbert-Schmidt distance between the estimator and the true states. So, an optimal SQPT can be realized by preparing both the inputs and the measurements as the symmetric IC-POVM.

  6. Tomography increases key rates of quantum-key-distribution protocols

    E-Print Network [OSTI]

    Shun Watanabe; Ryutaroh Matsumoto; Tomohiko Uyematsu

    2008-07-22T23:59:59.000Z

    We construct a practically implementable classical processing for the BB84 protocol and the six-state protocol that fully utilizes the accurate channel estimation method, which is also known as the quantum tomography. Our proposed processing yields at least as high key rate as the standard processing by Shor and Preskill. We show two examples of quantum channels over which the key rate of our proposed processing is strictly higher than the standard processing. In the second example, the BB84 protocol with our proposed processing yields a positive key rate even though the so-called error rate is higher than the 25% limit.

  7. Relation between quantum tomography and optical Fresnel transform

    E-Print Network [OSTI]

    Hong-yi Fan; Li-yun Hu

    2008-01-13T23:59:59.000Z

    Corresponding to optical Fresnel transformation characteristic of ray transfer matrix elements (A;B;C;D); AD-BC = 1, there exists Fresnel operator F(A;B;C;D) in quantum optics, we show that under the Fresnel transformation the pure position density |x>_rs,rs__rs,rs_Fresnel quadrature phase is the tomography (Radon transform of Wigner function), and the tomogram of a state |phi> is just the wave function of its Fresnel transformed state F|phi>, i.e. rs_= . Similarly, we find F|p>_rs,rs_

  8. Effect of Contrast Agent Charge on Visualization of Articular Cartilage Using Computed Tomography: Exploiting Electrostatic Interactions for Improved

    E-Print Network [OSTI]

    Effect of Contrast Agent Charge on Visualization of Articular Cartilage Using Computed Tomography such as those found in cartilage. Here, we report the synthesis of new iodinated cationic computed tomography

  9. Localization of Competing Metals (Ni, Co, and Zn) in Alyssum using micro-XRF and Tomography. (3564)

    E-Print Network [OSTI]

    Sparks, Donald L.

    Localization of Competing Metals (Ni, Co, and Zn) in Alyssum using micro-XRF and Tomography. (3564 and observed metal localization in root and shoot tissue using synchrotron based micro-XRF and tomography

  10. WIND TOMOGRAPHY IN BINARY SYSTEMS O.Knill, R.Dgani and M.Vogel

    E-Print Network [OSTI]

    Knill, Oliver

    WIND TOMOGRAPHY IN BINARY SYSTEMS O.Knill, R.Dgani and M.Vogel ETH-Zurich, CH-8092, Switzerland method is particularly suitable for determining the velocity laws of stellar winds. 1. WIND TOMOGRAPHY AND ABEL'S INTEGRAL Binary systems in which a compact, point-like radiation source shines through the wind

  11. Photoacoustic tomography of biological tissues with high cross-section resolution: Reconstruction and experiment

    E-Print Network [OSTI]

    Wang, Lihong

    27 November 2002 A modified back-projection approach deduced from an exact reconstruction solution was applied to our photoacoustic tomography of the optical absorption in biological tissues. Pulses from a Ti:sap a spatial resolution around 10 m.8 All of the above photoacoustic tomography systems can be categorized

  12. Electrical impedance tomography and Calderon's Department of Mathematics, University of Washington, Seattle, WA 98195, USA

    E-Print Network [OSTI]

    Uhlmann, Gunther

    Electrical impedance tomography and Calder´on's problem G Uhlmann Department of Mathematics, University of Washington, Seattle, WA 98195, USA E-mail: gunther@math.washington.edu Abstract. We survey mathematical developments in the inverse method of Electrical Impedance Tomography which consists

  13. Analysis of hydraulic tomography using temporal moments of drawdown recovery data

    E-Print Network [OSTI]

    Daniels, Jeffrey J.

    Analysis of hydraulic tomography using temporal moments of drawdown recovery data Junfeng Zhu 2006. [1] Transient hydraulic tomography (THT) is a potentially cost-effective and high- resolution technique for mapping spatial distributions of the hydraulic conductivity and specific storage in aquifers

  14. Hydraulic conductivity imaging from 3-D transient hydraulic tomography at several pumping/observation densities

    E-Print Network [OSTI]

    Barrash, Warren

    Hydraulic conductivity imaging from 3-D transient hydraulic tomography at several pumping August 2013; accepted 7 September 2013; published 13 November 2013. [1] 3-D Hydraulic tomography (3-D HT (primarily hydraulic conductivity, K) is estimated by joint inversion of head change data from multiple

  15. Scanning thermoacoustic tomography in biological tissue Geng Ku and Lihong V. Wanga)

    E-Print Network [OSTI]

    Wang, Lihong

    Scanning thermoacoustic tomography in biological tissue Geng Ku and Lihong V. Wanga) Optical-induced thermoacoustic tomography was explored to image biological tissue. Short microwave pulses irradiated tissue to generate acoustic waves by thermoelastic expansion. The microwave-induced thermoacoustic waves were

  16. Pulsed-microwave-induced thermoacoustic tomography: Filtered backprojection in a circular measurement configuration

    E-Print Network [OSTI]

    Wang, Lihong

    Pulsed-microwave-induced thermoacoustic tomography: Filtered backprojection in a circular-microwave-induced thermoacoustic tomography in biological tissues is pre- sented. A filtered backprojection algorithm based on rigorous theory is used to reconstruct the cross-sectional image from a thermoacoustic measurement

  17. Determining both sound speed and internal source in thermo- and photo-acoustic tomography

    E-Print Network [OSTI]

    Hongyu Liu; Gunther Uhlmann

    2015-02-04T23:59:59.000Z

    This paper concerns thermoacoustic tomography and photoacoustic tomography, two couple-physics imaging modalities that attempt to combine the high resolution of ultrasound and the high contrast capabilities of electromagnetic waves. We give sufficient conditions to recover both the sound speed of the medium being probed and the source.

  18. PERTURBATION-BASED ERROR ANALYSIS OF ITERATIVE IMAGE RECONSTRUCTION ALGORITHM FOR X-RAY COMPUTED TOMOGRAPHY

    E-Print Network [OSTI]

    Fessler, Jeffrey A.

    -ray computed tomography. The effects of the quantization error in forward-projection, back computed tomography (CT) have been proposed to improve image quality and reduce dose [1]. These methodsPERTURBATION-BASED ERROR ANALYSIS OF ITERATIVE IMAGE RECONSTRUCTION ALGORITHM FOR X-RAY COMPUTED

  19. Penalized Weighted Least-Squares Approach for Low-Dose X-Ray Computed Tomography

    E-Print Network [OSTI]

    Penalized Weighted Least-Squares Approach for Low-Dose X- Ray Computed Tomography Jing Wang*1, noise-resolution tradeoff, ROC curve. 1. INTRODUCTION Low-dose X-ray computed tomography (CT) imaging Military Medical University, Xi'an, Shaanxi 710032, China ABSTRACT The noise of low-dose computed

  20. Using X-ray computed tomography in hydrology: systems, resolutions, and limitations

    E-Print Network [OSTI]

    Wildenschild, Dorthe

    Using X-ray computed tomography in hydrology: systems, resolutions, and limitations D to characterize phase distribution and pore geometry in porous media using non-destructive X-ray computed tomography (CT). We present qualitative and quantitative CT results for partially saturated media, obtained

  1. Poly(iohexol) Nanoparticles As Contrast Agents for in Vivo Xray Computed Tomography Imaging

    E-Print Network [OSTI]

    Cheng, Jianjun

    Poly(iohexol) Nanoparticles As Contrast Agents for in Vivo Xray Computed Tomography Imaging Qian for in vivo X-ray computed tomography (CT) imaging. Compared to conventional small-molecule contrast agents with improved diagnosis accuracy over a broad time frame without multiple administrations. X-ray computed

  2. Quantitative Computed Tomography Analysis of Local Chemotherapy in Liver Tissue After

    E-Print Network [OSTI]

    Gao, Jinming

    Quantitative Computed Tomography Analysis of Local Chemotherapy in Liver Tissue After; controlled release drug delivery; radiofrequency ablation; computed tomography. © AUR, 2004 Acad Radiol 2004, MS, David L. Wilson, PhD, John R. Haaga, MD, Jinming Gao, PhD Rationale and Objectives. Computed

  3. Computer representation of the model covariance function resulting from travel-time tomography

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    Computer representation of the model covariance function resulting from travel-time tomography Lud a supplement to the paper by Klime#20;s (2002b) on the stochastic travel{time tomography. It contains brief covariance function is a function of 6 coordinates with pro- nounced singularities. The computer

  4. Classification and volumetric analysis of temporal bone pneumatization using cone beam computed tomography

    E-Print Network [OSTI]

    Terasaki, Mark

    bone pneumatization in adults using cone beam computed tomography (CBCT) scans. Study Design. A total Oral Pathol Oral Radiol 2014;117:376-384) The advances in cone beam computed tomography (CBCT) overClassification and volumetric analysis of temporal bone pneumatization using cone beam computed

  5. Frequency domain phase-resolved optical Doppler and Doppler variance tomography

    E-Print Network [OSTI]

    Chen, Zhongping

    ), is capable of measuring micro- flows using the optical Doppler effect [1,2]. Early ODT systems were unableFrequency domain phase-resolved optical Doppler and Doppler variance tomography Lei Wang a phase-resolved optical Doppler tomography (ODT) was developed with Doppler variance imag- ing capability

  6. Seismic tomography constraints on reconstructing the Philippine Sea Plate and its margin

    E-Print Network [OSTI]

    Handayani, Lina

    2005-02-17T23:59:59.000Z

    ............................................................. 36 Japan Subduction Zone.................................................................. 41 Izu-Bonin Subduction Zone........................................................... 41 Ryukyu Subduction Zone.................................. 38 3.5 P-wave seismic tomography cross sections across Japan (C), Izu-Bonin(D), Mariana (E) and Java (F)......................................... 39 3.6 Tomography cross sections 1 to 5...

  7. Using computerized tomography to determine ionospheric structures. Part 1, Notivation and basic approaches

    SciTech Connect (OSTI)

    Vittitoe, C.N.

    1993-08-01T23:59:59.000Z

    Properties of the ionosphere are reviewed along with its correlations with other geophysical phenomena and with applications of ionospheric studies to communication, navigation, and surveillance systems. Computer tomography is identified as a method to determine the detailed, three-dimensional distribution of electron density within the ionosphere. Several tomography methods are described, with a basic approach illustrated by an example. Limitations are identified.

  8. Cloud tomography: Role of constraints and a new algorithm Dong Huang,1

    E-Print Network [OSTI]

    Cloud tomography: Role of constraints and a new algorithm Dong Huang,1 Yangang Liu,1 and Warren 2008. [1] Retrieving spatial distributions of cloud liquid water content from limited-angle emission data (passive microwave cloud tomography) is ill-posed, and a small inaccuracy in the data and

  9. Data-driven classification of ventilated lung tissues using electrical impedance tomography

    E-Print Network [OSTI]

    Adler, Andy

    Data-driven classification of ventilated lung tissues using electrical impedance tomography Camille for identifying ventilated lung regions utilizing electrical impedance tomography (EIT) images rely on dividing of a data-driven classification method to identify ventilated lung ROI based on forming k clusters from

  10. Automatic 3D Registration of Lung Surfaces in Computed Tomography Scans

    E-Print Network [OSTI]

    Automatic 3D Registration of Lung Surfaces in Computed Tomography Scans Margrit Betke, PhD1 scheme until the registration performance is sufficient. We applied our method to register the 3D lung computed tomography (CT) has become a well-established means of diag- nosing primary lung cancer

  11. Automatic 3D Registration of Lung Surfaces in Computed Tomography Scans

    E-Print Network [OSTI]

    Automatic 3D Registration of Lung Surfaces in Computed Tomography Scans Margrit Betke, PhD 1 lung surfaces of 11 pairs of chest CT scans and report promising registration performance. 1 1 Introduction Chest computed tomography (CT) has become a well­established means of diag­ nosing primary lung

  12. Introducing Minimum Fisher Regularisation Tomography to Bolometric and Soft X-ray Diagnostic Systems of the COMPASS Tokamak

    E-Print Network [OSTI]

    Introducing Minimum Fisher Regularisation Tomography to Bolometric and Soft X-ray Diagnostic Systems of the COMPASS Tokamak

  13. Microwave-induced thermoacoustic tomography using multi-sector Minghua Xu, Geng Ku, and Lihong V. Wanga)

    E-Print Network [OSTI]

    Wang, Lihong

    Microwave-induced thermoacoustic tomography using multi-sector scanning Minghua Xu, Geng Ku A study of microwave-induced thermoacoustic tomography of inhomogeneous tissues using multi- sector of Physicists in Medicine. DOI: 10.1118/1.1395037 Key words: microwave, thermoacoustics, tomography, imaging

  14. Papers by Our Team Wang G, Vannier MW: Bolus-chasing angiography with adaptive real-time computed tomography. US

    E-Print Network [OSTI]

    Wang, Ge

    chasing computed tomography (CT) angiography. US patent publication 20060178836, Aug. 10, 2006 Ye Y, Wang:1-20, 2007 Cai Z, McCabe R, Wang G, Bai EW: Bolus chasing computed tomography angiography using local maximum, McCabe R, Wang G: An adaptive optimal control design for bolus chasing computed tomography

  15. Prospects for quantitative computed tomography imaging in the presence of foreign metal bodies using statistical image reconstruction

    E-Print Network [OSTI]

    O'Sullivan, Joseph A.

    Prospects for quantitative computed tomography imaging in the presence of foreign metal bodies September 2002 X-ray computed tomography CT images of patients bearing metal intracavitary applicators of Physicists in Medicine. DOI: 10.1118/1.1509443 Key words: x-ray transmission computed tomography, metal

  16. Simultaneous CT and SPECT tomography using CZT detectors

    DOE Patents [OSTI]

    Paulus, Michael J. (Knoxville, TN); Sari-Sarraf, Hamed (Lubbock, TX); Simpson, Michael L. (Knoxville, TN); Britton, Jr., Charles L. (Alcoa, TN)

    2002-01-01T23:59:59.000Z

    A method for simultaneous transmission x-ray computed tomography (CT) and single photon emission tomography (SPECT) comprises the steps of: injecting a subject with a tracer compound tagged with a .gamma.-ray emitting nuclide; directing an x-ray source toward the subject; rotating the x-ray source around the subject; emitting x-rays during the rotating step; rotating a cadmium zinc telluride (CZT) two-sided detector on an opposite side of the subject from the source; simultaneously detecting the position and energy of each pulsed x-ray and each emitted .gamma.-ray captured by the CZT detector; recording data for each position and each energy of each the captured x-ray and .gamma.-ray; and, creating CT and SPECT images from the recorded data. The transmitted energy levels of the x-rays lower are biased lower than energy levels of the .gamma.-rays. The x-ray source is operated in a continuous mode. The method can be implemented at ambient temperatures.

  17. Statistical analysis of sampling methods in quantum tomography

    E-Print Network [OSTI]

    Thomas Kiesel

    2012-06-07T23:59:59.000Z

    In quantum physics, all measured observables are subject to statistical uncertainties, which arise from the quantum nature as well as the experimental technique. We consider the statistical uncertainty of the so-called sampling method, in which one estimates the expectation value of a given observable by empirical means of suitable pattern functions. We show that if the observable can be written as a function of a single directly measurable operator, the variance of the estimate from the sampling method equals to the quantum mechanical one. In this sense, we say that the estimate is on the quantum mechanical level of uncertainty. In contrast, if the observable depends on non-commuting operators, e.g. different quadratures, the quantum mechanical level of uncertainty is not achieved. The impact of the results on quantum tomography is discussed, and different approaches to quantum tomographic measurements are compared. It is shown explicitly for the estimation of quasiprobabilities of a quantum state, that balanced homodyne tomography does not operate on the quantum mechanical level of uncertainty, while the unbalanced homodyne detection does.

  18. LMFBR fuel bundle distortion characterization using neutron tomography and potting

    SciTech Connect (OSTI)

    Betten, P.R.; Tow, D.M.

    1984-05-01T23:59:59.000Z

    A standard liquid metal fast breeder reactor (LMFBR) subassembly used in the Experimental Breeder Reactor II (EBRII) was investigated for fuel bundle distortion by both nondestructive and destructive methods, and the results from both methods were compared. The nondestructive method employed neutron tomography to reconstruct the locations of fuel elements through the use of a maximum entropy reconstruction algorithm known as MENT. The destructive method consisted of ''potting'' (a technique that embeds and permanently fixes the fuel elements in a solid matrix) the subassembly and then cutting and polishing the individual sections. The comparison indicated that the tomography reconstruction provided good results in describing the bundle geometry and spacer-wire locations, with the overall resolution being on the order of a spacer-wire diameter. A dimensional consistency check indicated that the element and spacer-wire dimensions were accurately reproduced in the reconstruction. It was found that in situ fuel elements deform axially in a helical spiral and that the reconstruction was able to identify this helical distortion to within approximately half of a spacerwire diameter.

  19. VSoE RIF Report: Micro-Tomography P.I.: Young H. Cho, Research Assistant Professor, Dept of EE/Dept of CS

    E-Print Network [OSTI]

    Zhou, Chongwu

    the underwater physical phenomena accurately at higher resolution using a network of collaborative, low-cost tomography (micro-tomography), (2) deep water Micro-tomography, and (3) ultra-low power sensor PHY to the expense of buoys, floats or robotic probes. By performing acoustic tomography between shore or buoy

  20. Novel Application of X-ray Computed Tomography: Determination of Gas/Liquid Contact Area and Liquid Holdup in Structured Packing

    E-Print Network [OSTI]

    Eldridge, R. Bruce

    Novel Application of X-ray Computed Tomography: Determination of Gas/Liquid Contact Area and Liquid Company, 1 Neumann Way-M/D Q8, Cincinnati, Ohio 45215 X-ray computed tomography (CT) was utilized Principles of X-ray Computed Tomography. X-ray computed tomography (CT) is used to noninvasively

  1. Data fusion in neutron and X-ray computed tomography

    SciTech Connect (OSTI)

    Schrapp, Michael J. [Siemens AG, Corporate Technology, Otto-Hahn-Ring 6, 81739 Munich (Germany); Physik Department E21, Technische Universität München, James-Franck-Strasse 1, 85747 Garching (Germany); Goldammer, Matthias [Siemens AG, Corporate Technology, Otto-Hahn-Ring 6, 81739 Munich (Germany); Schulz, Michael [Physik Department E21, Technische Universität München, James-Franck-Strasse 1, 85747 Garching (Germany); Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München, Lichtenbergstrasse 1, 85747 Garching (Germany); Issani, Siraj; Bhamidipati, Suryanarayana [Siemens AG, Corporate Technology, Bangalore (India); Böni, Peter [Physik Department E21, Technische Universität München, James-Franck-Strasse 1, 85747 Garching (Germany)

    2014-10-28T23:59:59.000Z

    We present a fusion methodology between neutron and X-ray computed tomography (CT). On the one hand, the inspection by X-ray CT of a wide class of multimaterials in non-destructive testing applications suffers from limited information of object features. On the other hand, neutron imaging can provide complementary data in such a way that the combination of both data sets fully characterizes the object. In this contribution, a novel data fusion procedure, called Fusion Regularized Simultaneous Algebraic Reconstruction Technique, is developed where the X-ray reconstruction is modified to fulfill the available data from the imaging with neutrons. The experiments, which were obtained from an aluminum profile containing a steel screw, and attached carbon fiber plates demonstrate that the image quality in CT can be significantly improved when the proposed fusion method is used.

  2. Fourier-based magnetic induction tomography for mapping resistivity

    SciTech Connect (OSTI)

    Puwal, Steffan; Roth, Bradley J. [Department of Physics, Oakland University, Rochester, Michigan 48309 (United States)

    2011-01-01T23:59:59.000Z

    Magnetic induction tomography is used as an experimental tool for mapping the passive electromagnetic properties of conductors, with the potential for imaging biological tissues. Our numerical approach to solving the inverse problem is to obtain a Fourier expansion of the resistivity and the stream functions of the magnetic fields and eddy current density. Thus, we are able to solve the inverse problem of determining the resistivity from the applied and measured magnetic fields for a two-dimensional conducting plane. When we add noise to the measured magnetic field, we find the fidelity of the measured to the true resistivity is quite robust for increasing levels of noise and increasing distances of the applied and measured field coils from the conducting plane, when properly filtered. We conclude that Fourier methods provide a reliable alternative for solving the inverse problem.

  3. Iterative methods for dose reduction and image enhancement in tomography

    DOE Patents [OSTI]

    Miao, Jianwei; Fahimian, Benjamin Pooya

    2012-09-18T23:59:59.000Z

    A system and method for creating a three dimensional cross sectional image of an object by the reconstruction of its projections that have been iteratively refined through modification in object space and Fourier space is disclosed. The invention provides systems and methods for use with any tomographic imaging system that reconstructs an object from its projections. In one embodiment, the invention presents a method to eliminate interpolations present in conventional tomography. The method has been experimentally shown to provide higher resolution and improved image quality parameters over existing approaches. A primary benefit of the method is radiation dose reduction since the invention can produce an image of a desired quality with a fewer number projections than seen with conventional methods.

  4. 3D Jet Tomography of the Twisted Color Glass Condensate

    E-Print Network [OSTI]

    A. Adil; M. Gyulassy; T. Hirano

    2005-09-23T23:59:59.000Z

    Jet Tomography is proposed as a new test of Color Glass Condensate (CGC) initial conditions in non-central $A+A$ collisions. The $k_{T}$ factorized CGC formalism is used to calculate the rapidity twist in the reaction plane of both the bulk low $p_T 6$ GeV partons. Unlike conventional perturbative QCD, the initial high $p_{T}$ CGC gluons are shown to be twisted even further away from the beam axis than the the low $p_T$ bulk at high rapidities $|\\eta|>2$. Differential directed flow $v_{1}(p_{T}>6,|\\eta|>2)$ is proposed to test this novel high $p_T$ rapidity twist predicted by the CGC model.

  5. Application of a nudging technique to thermoacoustic tomography

    E-Print Network [OSTI]

    Bonnefond, Xavier

    2011-01-01T23:59:59.000Z

    ThermoAcoustic Tomography (TAT) is a promising, non invasive, medical imaging technique whose inverse problem can be formulated as an initial condition reconstruction. In this paper, we introduce a new algorithm originally designed to correct the state of an evolution model, the \\emph{back and forth nudging} (BFN), for the TAT inverse problem. We show that the flexibility of this algorithm enables to consider a quite general framework for TAT. The backward nudging algorithm is studied and a proof of the geometrical convergence rate of the BFN is given. A method based on Conjugate Gradient (CG) is also introduced. Finally, numerical experiments validate the theoretical results with a better BFN convergence rate for more realistic setups and a comparison is established between BFN, CG and a usual inversion method.

  6. Real time evaluation of overranging in helical computed tomography

    E-Print Network [OSTI]

    Trevisan, Diego; Ravanelli, Daniele; Valentini, Aldo

    2014-01-01T23:59:59.000Z

    Overranging or overscanning increases the dose delivered to patients undergoing helical Computed Tomography examinations. In order to reduce it, nowadays most of the multidetector tomographs close the X-ray beam aperture at the scan extremes. This technical innovation, usually referred to as dynamic or adaptive collimation, also influences the overranging assessment methods. In particular, the film free approach proposed in previous studies is not suitable for these modern tomographs. The present study aims to introduce a new method of estimating overranging with real time dosimetry, even suitable for tomographs equipped with adaptive collimation. The approach proposed is very easy to implement and time saving because only a pencil chamber is required. It is also equivalent in precision and in accuracy to the film based one, considered an absolute benchmark.

  7. Initial results of finger imaging using Photoacoustic Computed Tomography

    E-Print Network [OSTI]

    van Es, Peter; Moens, Hein J Bernelot; Steenbergen, Wiendelt; Manohar, Srirang

    2014-01-01T23:59:59.000Z

    We present a photoacoustic computed tomography investigation on a healthy human finger, to image blood vessels with a focus on vascularity across the interphalangeal joints. The cross-sectional images were acquired using an imager specifically developed for this purpose. The images show rich detail of the digital blood vessels with diameters between 100 $\\mu$m and 1.5 mm in various orientations and at various depths. Different vascular layers in the skin including the subpapillary plexus could also be visualized. Acoustic reflections on the finger bone of photoacoustic signals from skin were visible in sequential slice images along the finger except at the location of the joint gaps. Not unexpectedly, the healthy synovial membrane at the joint gaps was not detected due to its small size and normal vascularization. Future research will concentrate on studying digits afflicted with rheumatoid arthritis to detect the inflamed synovium with its heightened vascularization, whose characteristics are potential marke...

  8. Electrical resistance tomography from measurements inside a steel cased borehole

    DOE Patents [OSTI]

    Daily, William D. (Livermore, CA); Schenkel, Clifford (Walnut Creek, CA); Ramirez, Abelardo L. (Pleasanton, CA)

    2000-01-01T23:59:59.000Z

    Electrical resistance tomography (ERT) produced from measurements taken inside a steel cased borehole. A tomographic inversion of electrical resistance measurements made within a steel casing was then made for the purpose of imaging the electrical resistivity distribution in the formation remotely from the borehole. The ERT method involves combining electrical resistance measurements made inside a steel casing of a borehole to determine the electrical resistivity in the formation adjacent to the borehole; and the inversion of electrical resistance measurements made from a borehole not cased with an electrically conducting casing to determine the electrical resistivity distribution remotely from a borehole. It has been demonstrated that by using these combined techniques, highly accurate current injection and voltage measurements, made at appropriate points within the casing, can be tomographically inverted to yield useful information outside the borehole casing.

  9. A metallography and x-ray tomography study of spall damage in ultrapure Al

    SciTech Connect (OSTI)

    Qi, M. L. [School of Science, Wuhan University of Technology, Wuhan, Hubei 430070 (China); HPSynC@Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Bie, B. X. [School of Science, Wuhan University of Technology, Wuhan, Hubei 430070 (China); The Peac Institute of Multiscale Sciences and Sichuan University, Chengdu, Sichuan 610207 (China); Zhao, F. P.; Fan, D.; Luo, S. N., E-mail: sluo@pims.ac.cn [The Peac Institute of Multiscale Sciences and Sichuan University, Chengdu, Sichuan 610207 (China); Hu, C. M. [HPSynC@Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); National Key Laboratory of Shock Wave and Detonation Physics, Chinese Academy of Engineering Physics, Mianyang, Sichuan 621900 (China); Ran, X. X. [School of Science, Wuhan University of Technology, Wuhan, Hubei 430070 (China); Xiao, X. H. [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Yang, W. G., E-mail: wenge@aps.anl.gov [HPSynC@Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Li, P. [National Key Laboratory of Shock Wave and Detonation Physics, Chinese Academy of Engineering Physics, Mianyang, Sichuan 621900 (China)

    2014-07-15T23:59:59.000Z

    We characterize spall damage in shock-recovered ultrapure Al with metallography and x-ray tomography. The measured damage profiles in ultrapure Al induced by planar impact at different shock strengths, can be described with a Gaussian function, and showed dependence on shock strengths. Optical metallography is reasonably accurate for damage profile measurements, and agrees within 10–25% with x-ray tomography. Full tomography analysis showed that void size distributions followed a power law with an exponent of ? = 1.5 ± 2.0, which is likely due to void nucleation and growth, and the exponent is considerably smaller than the predictions from percolation models.

  10. Process Tomography: An Option for the Enhancement of Packed Vapor-Liquid Contactor Model Development

    E-Print Network [OSTI]

    Eldridge, R. Bruce

    columns. Introduction Distillation is the dominant unit operation in the chemical process industry. Despite the classification of distillation as a mature technology, improvements in the design further advances in column internals design. The authors believe process tomography can yield

  11. Pulmonary Hypertension and Computed Tomography Measurement of Small Pulmonary Vessels in

    E-Print Network [OSTI]

    Pulmonary Hypertension and Computed Tomography Measurement of Small Pulmonary Vessels in Severe alteration of small pulmonary vessels is one of the characteristic features of pulmonary hypertension in chronic obstruc- tive pulmonary disease. The in vivo relationship between pulmonary hypertension

  12. Seismic tomography constraints on reconstructing the Philippine Sea Plate and its margin 

    E-Print Network [OSTI]

    Handayani, Lina

    2005-02-17T23:59:59.000Z

    show the distribution of high velocity anomalies in the mantle of the Western Pacific, and that they represent subducted slabs. Using these recent tomography data, distribution maps of subducted slabs in the mantle beneath and surrounding the Philippine...

  13. Barium Titanate Nanoparticles as Exogenous Contrast Agents in Second Harmonic Optical Coherence Tomography

    E-Print Network [OSTI]

    Pearson, Jeremy T

    2013-05-06T23:59:59.000Z

    I propose and demonstrate a method by which barium titanate nanoparticle clusters can be used as exogenous contrast agents in Second Harmonic Optical Coherence Tomography imaging systems to localize and highlight desired regions of tissue. SH...

  14. Optical coherence tomography based on intensity correlations of quasi-thermal light

    E-Print Network [OSTI]

    Zerom, Petros

    We show theoretically that the longitudinal resolution of conventional optical coherence tomography can be improved by a factor of radic2 when a two-photon (as opposed to a single-photon) sensitive detector is used, and ...

  15. Endoscopic optical coherence tomography for clinical studies in the gastrointestinal tract

    E-Print Network [OSTI]

    Tsai, Tsung-Han, Ph. D. Massachusetts Institute of Technology

    2013-01-01T23:59:59.000Z

    Optical coherence tomography (OCT) performs micrometer-scale, cross-sectional and three dimensional imaging by measuring the echo time delay of backscattered light. OCT imaging is performed using low-coherence interferometry. ...

  16. High-resolution three-dimensional optical coherence tomography imaging of kidney microanatomy ex vivo

    E-Print Network [OSTI]

    Chen, Yu

    Optical coherence tomography (OCT) is an emerging medical imaging technology that enables high-resolution, noninvasive, cross-sectional imaging of microstructure in biological tissues in situ and in real time. When combined ...

  17. Measurement of bubble sizes in fluidised beds using electrical capacitance tomography

    E-Print Network [OSTI]

    Chandrasekera, T. C.; Li, Y.; Moody, D.; Schnellmann, M. A.; Dennis, J. S.; Holland, D. J.

    2015-01-13T23:59:59.000Z

    Electrical capacitance tomography (ECT) provides a means for non-invasively imaging multiphase flows, such as those in fluidised beds. Traditionally ECT images are reconstructed using the assumption that the distribution of permittivity varies...

  18. Applications of Fourier Domain Mode Locked lasers for optical coherence tomography imaging

    E-Print Network [OSTI]

    Adler, Desmond Christopher, 1978-

    2009-01-01T23:59:59.000Z

    Optical coherence tomography (OCT) is a micrometer-resolution imaging technique that produces cross-sectional images of sample microstructure by measuring the amplitude and echo time delay of backscattered light. OCT imaging ...

  19. HFSS code for Thermoacoustic Tomography Testbed Liping Yan, co-investigator (sherryyan05@gmail.com)

    E-Print Network [OSTI]

    Patch, Sarah

    HFSS code for Thermoacoustic Tomography Testbed Liping Yan, co-investigator (sherryyan05@gmail to design the UW-Milwaukee Thermoacoustic Testbed. "Testbed.hfss" can be run material, testbed length, etc. The UWM thermoacoustic testbed is essentially

  20. Feasibility study on bonding quality inspection of microfluidic devices by optical coherence tomography

    E-Print Network [OSTI]

    Li, Shiguang

    This paper reports the feasibility of optical coherence tomography (OCT) technology for inspection of bonding quality of microfluidic devices in manufacturing environments. A compact optical-fiber–based OCT is developed ...

  1. P- and S- wave tomography of the crust and uppermost mantle in China and surrounding areas

    E-Print Network [OSTI]

    Sun, Youshun, 1970-

    2005-01-01T23:59:59.000Z

    This thesis involves inverting the seismic structure of the crust and uppermost mantle in China from the P- and S-wave travel-time tomography. The main contributions of this research are: 1) introducing the adaptive moving ...

  2. Spectral/ Fourier domain Doppler Optical Coherence Tomography in the rodent retina

    E-Print Network [OSTI]

    Liu, Jonathan Jaoshin

    2008-01-01T23:59:59.000Z

    Optical Coherence Tomography (OCT) is an emerging imaging technique based on low-coherence interferometry for noninvasive, high- resolution, cross-sectional imaging in a variety of biomedical fields. In ophthalmology, OCT ...

  3. Swept source / Fourier domain polarization sensitive optical coherence tomography with a passive polarization delay unit

    E-Print Network [OSTI]

    Baumann, Bernhard

    Polarization sensitive optical coherence tomography (PS-OCT) is a functional imaging method that provides additional contrast using the light polarizing properties of a sample. This manuscript describes PS-OCT based on ...

  4. Design and Optimize a Two Color Fourier Domain Pump Probe Optical Coherence Tomography System

    E-Print Network [OSTI]

    Jacob, Desmond

    2010-01-16T23:59:59.000Z

    processes at a molecular level. Pump probe spectroscopy has been used extensively to study the molecular properties of poorly fluorescing biomolecules, because it utilizes the known absorption spectrum of these chromophores. Optical Coherence Tomography (OCT...

  5. Advances in Optical Coherence Tomography and Microscopy for endoscopic applications and functional neuroimaging

    E-Print Network [OSTI]

    Aguirre, Aaron Dominic, 1977-

    2008-01-01T23:59:59.000Z

    Optical Coherence Tomography (OCT) is a developing medical imaging technology that generates micron resolution cross-sectional images of subsurface internal tissue structure in situ and in real time, without the need to ...

  6. Method for Quantitative Study of Airway Functional Microanatomy Using Micro-Optical Coherence Tomography

    E-Print Network [OSTI]

    Diephuis, Bradford J.

    We demonstrate the use of a high resolution form of optical coherence tomography, termed micro-OCT (?OCT), for investigating the functional microanatomy of airway epithelia. ?OCT captures several key parameters governing ...

  7. Atherosclerotic tissue characterization in vivo by optical coherence tomography attenuation imaging

    E-Print Network [OSTI]

    Tearney, Guillermo J.

    Optical coherence tomography (OCT) is rapidly becoming the method of choice for assessing arterial wall pathology in vivo. Atherosclerotic plaques can be diagnosed with high accuracy, including measurement of the thickness ...

  8. Review paper Seismic interferometry and ambient noise tomography in the British Isles

    E-Print Network [OSTI]

    Review paper Seismic interferometry and ambient noise tomography in the British Isles Heather. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 2. Theory and method of seismic interferometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79 4.2. Seismic interferometry across the Scottish Highlands

  9. Progress toward scalable tomography of quantum maps using twirling-based methods and information hierarchies

    E-Print Network [OSTI]

    Lopez, Cecilia Carolina

    We present in a unified manner the existing methods for scalable partial quantum process tomography. We focus on two main approaches: the one presented in Bendersky et al. [Phys. Rev. Lett. 100, 190403 (2008)] and the ones ...

  10. Spectral oximetry assessed with high-speed ultra-high-resolution optical coherence tomography

    E-Print Network [OSTI]

    Kagemann, Larry

    We use Fourier domain optical coherence tomography (OCT) data to assess retinal blood oxygen saturation. Three-dimensional disk-centered retinal tissue volumes were assessed in 17 normal healthy subjects. After removing ...

  11. A microwave tomography system using a tunable mirror for beam steering

    SciTech Connect (OSTI)

    Tayebi, A. [Department of Electrical and Computer Engineering, College of Engineering, Michigan State University, East Lansing, MI 48824 (United States); Non-Destructive Evaluation Laboratory, Michigan State University, East Lansing, MI 48824 (United States); Department of Physic (United States); Tang, J. [Department of Electrical and Computer Engineering, College of Engineering, Michigan State University, East Lansing, MI 48824 (United States); Paladhi, P. Roy; Udpa, L.; Udpa, S. [Department of Electrical and Computer Engineering, College of Engineering, Michigan State University, East Lansing, MI 48824 (United States); Non-Destructive Evaluation Laboratory, Michigan State University, East Lansing, MI 48824 (United States)

    2014-02-18T23:59:59.000Z

    Microwave tomography is a fast-growing technique in the fields of NDE and medical industry. This paper presents a new microwave tomography system which reduces the complexities of conventional microwave imaging systems by utilizing a reconfigurable mirror, a tunable reflectarray antenna. In order to build a tunable reflectarray with beam steering capabilities, the unit cell characteristics should dynamically alter. Modelling and experimental results of a single unit cell are presented in this work.

  12. Severity mapping of the proximal femur: a new method for assessing hip osteoarthritis with computed tomography

    E-Print Network [OSTI]

    Turmezei, T. D.; Lomas, D. J.; Hopper, M. A.; Poole, K. E. S.

    2014-01-01T23:59:59.000Z

    TITLE Severity mapping of the proximal femur: a new method for assessing hip osteoarthritis with computed tomography AUTHORS Turmezei TD1,2,3,*, Lomas DJ2, Hopper MA2, Poole KES3 * = corresponding author AFFILIATIONS 1 = Department... , Hills Road, Cambridge, CB2 0QQ, UK KEY WORDS osteoarthritis; hip joint; computed tomography; phenotyping. (3-6 words) RUNNING HEADLINE Severity mapping of hip osteoarthritis (40 characters) Title Page & Abstract ABSTRACT Objective Plain...

  13. Fuzzy Modeling of Electrical Impedance Tomography Image of the Lungs

    E-Print Network [OSTI]

    Tanaka, Harki; Galizia, Mauricio Stanzione; Sobrinho, Joao Batista Borges; Amato, Marcelo Britto Passos

    2007-01-01T23:59:59.000Z

    Electrical Impedance Tomography (EIT) is a functional imaging method that is being developed for bedside use in critical care medicine. Aiming at improving the chest anatomical resolution of EIT images we developed a fuzzy model based on EIT high temporal resolution and the functional information contained in the pulmonary perfusion and ventilation signals. EIT data from an experimental animal model were collected during normal ventilation and apnea while an injection of hypertonic saline was used as a reference . The fuzzy model was elaborated in three parts: a modeling of the heart, a pulmonary map from ventilation images and, a pulmonary map from perfusion images. Image segmentation was performed using a threshold method and a ventilation/perfusion map was generated. EIT images treated by the fuzzy model were compared with the hypertonic saline injection method and CT-scan images, presenting good results in both qualitative (the image obtained by the model was very similar to that of the CT-scan) and quant...

  14. Measurement strategy for rectangular electrical capacitance tomography sensor

    SciTech Connect (OSTI)

    Ye, Jiamin; Ge, Ruihuan; Qiu, Guizhi; Wang, Haigang [Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing, 100190 (China)

    2014-04-11T23:59:59.000Z

    To investigate the influence of the measurement strategy for the rectangular electrical capacitance tomography (ECT) sensor, a Finite Element Method (FEM) is utilized to create the model for simulation. The simulation was carried out using COMSOL Multiphysics(trade mark, serif) and Matlab(trade mark, serif). The length-width ratio of the rectangular sensing area is 5. Twelve electrodes are evenly arranged surrounding the pipe. The covering ratio of the electrodes is 90%. The capacitances between different electrode pairs are calculated for a bar distribution. The air of the relative permittivity 1.0 and the material of the permittivity 3.0 are used for the calibration. The relative permittivity of the second phase is 3.0. The noise free and noise data are used for the image reconstruction using the Linear Back Projection (LBP). The measurement strategies with 1-, 2- and 4- electrode excitation are compared using the correlation coefficient. Preliminary results show that the measurement strategy with 2-electrode excitation outperforms other measurement strategies with 1- or 4-electrode excitation.

  15. Quantum process tomography of unitary and near-unitary maps

    E-Print Network [OSTI]

    Charles H. Baldwin; Amir Kalev; Ivan H. Deutsch

    2014-04-22T23:59:59.000Z

    We study quantum process tomography given the prior information that the map is a unitary or close to a unitary process. We show that a unitary map on a $d$-level system is completely characterized by a minimal set of $d^2{+}d$ elements associated with a collection of POVMs, in contrast to the $d^4{-}d^2$ elements required for a general completely positive trace-preserving map. To achieve this lower bound, one must probe the map with a particular set of $d$ pure states. We further compare the performance of different compressed sensing algorithms used to reconstruct a near-unitary process from such data. We find that when we have accurate prior information, an appropriate compressed sensing method reduces the required data needed for high-fidelity estimation, and different estimators applied to the same data are sensitive to different types of noise. Compressed sensing techniques can therefore be used both as indicators of error models and to validate the use of the prior assumptions.

  16. Artifact reduction in industrial computed tomography via data fusion

    SciTech Connect (OSTI)

    Schrapp, Michael; Goldammer, Matthias; Stephan, Jürgen [Siemens AG, Corporate Technology, Otto-Hahn-Ring 6, 81739 Munich (Germany)

    2014-02-18T23:59:59.000Z

    As the most stressed part of a gas turbine the first row of turbine blades is not only a challenge for the materials used. Also the testing of these parts have to meet the highest standards. Computed tomography (CT) as the technique which could reveal the most details also provides the biggest challenges [1]: A full penetration of large sized turbine blades is often only possible at high X-ray voltages causing disproportional high costs. A reduction of the X-ray voltage is able to reduce these arising costs but yields non penetration artifacts in the reconstructed CT image. In most instances, these artifacts manifests itself as blurred and smeared regions at concave edges due to a reduced signal to noise ratio. In order to complement the missing information and to increase the overall image quality of our reconstruction, we use further imaging modalities such as a 3-D Scanner and ultrasonic imaging. A 3-D scanner is easy and cost effective to implement and is able to acquire all relevant data simultaneously with the CT projections. If, however, the interior structure is of supplemental interest, an ultrasonic imaging method is additionally used. We consider this data as a priori knowledge to employ them in an iterative reconstruction. To do so, standard iterative reconstruction methods are modified to incorporate the a priori data in a regularization approach in combination with minimizing the total variation of our image. Applying this procedure on turbine blades, we are able to reduce the apparent artifacts almost completely.

  17. Using electrical resistance tomography to map subsurface temperatures

    DOE Patents [OSTI]

    Ramirez, Abelardo L. (Pleasanton, CA); Chesnut, Dwayne A. (San Francisco, CA); Daily, William D. (Livermore, CA)

    1994-01-01T23:59:59.000Z

    A method is provided for measuring subsurface soil or rock temperatures remotely using electrical resistivity tomography (ERT). Electrical resistivity measurements are made using electrodes implanted in boreholes driven into the soil and/or at the ground surface. The measurements are repeated as some process changes the temperatures of the soil mass/rock mass. Tomographs of electrical resistivity are calculated based on the measurements using Poisson's equation. Changes in the soil/rock resistivity can be related to changes in soil/rock temperatures when: (1) the electrical conductivity of the fluid trapped in the soil's pore space is low, (2) the soil/rock has a high cation exchange capacity and (3) the temperature changes are sufficiently high. When these three conditions exist the resistivity changes observed in the ERT tomographs can be directly attributed to changes in soil/rock temperatures. This method provides a way of mapping temperature changes in subsurface soils remotely. Distances over which the ERT method can be used to monitor changes in soil temperature range from tens to hundreds of meters from the electrode locations.

  18. Using electrical resistance tomography to map subsurface temperatures

    DOE Patents [OSTI]

    Ramirez, A.L.; Chesnut, D.A.; Daily, W.D.

    1994-09-13T23:59:59.000Z

    A method is provided for measuring subsurface soil or rock temperatures remotely using electrical resistivity tomography (ERT). Electrical resistivity measurements are made using electrodes implanted in boreholes driven into the soil and/or at the ground surface. The measurements are repeated as some process changes the temperatures of the soil mass/rock mass. Tomographs of electrical resistivity are calculated based on the measurements using Poisson's equation. Changes in the soil/rock resistivity can be related to changes in soil/rock temperatures when: (1) the electrical conductivity of the fluid trapped in the soil's pore space is low, (2) the soil/rock has a high cation exchange capacity and (3) the temperature changes are sufficiently high. When these three conditions exist the resistivity changes observed in the ERT tomographs can be directly attributed to changes in soil/rock temperatures. This method provides a way of mapping temperature changes in subsurface soils remotely. Distances over which the ERT method can be used to monitor changes in soil temperature range from tens to hundreds of meters from the electrode locations. 1 fig.

  19. Electrical resistance tomography using steel cased boreholes as electrodes

    DOE Patents [OSTI]

    Daily, William D. (Livermore, CA); Ramirez, Abelardo L. (Pleasanton, CA)

    1999-01-01T23:59:59.000Z

    An electrical resistance tomography method using steel cased boreholes as electrodes. The method enables mapping the electrical resistivity distribution in the subsurface from measurements of electrical potential caused by electrical currents injected into an array of electrodes in the subsurface. By use of current injection and potential measurement electrodes to generate data about the subsurface resistivity distribution, which data is then used in an inverse calculation, a model of the electrical resistivity distribution can be obtained. The inverse model may be constrained by independent data to better define an inverse solution. The method utilizes pairs of electrically conductive (steel) borehole casings as current injection electrodes and as potential measurement electrodes. The greater the number of steel cased boreholes in an array, the greater the amount of data is obtained. The steel cased boreholes may be utilized for either current injection or potential measurement electrodes. The subsurface model produced by this method can be 2 or 3 dimensional in resistivity depending on the detail desired in the calculated resistivity distribution and the amount of data to constain the models.

  20. Electrical resistance tomography using steel cased boreholes as electrodes

    DOE Patents [OSTI]

    Daily, W.D.; Ramirez, A.L.

    1999-06-22T23:59:59.000Z

    An electrical resistance tomography method is described which uses steel cased boreholes as electrodes. The method enables mapping the electrical resistivity distribution in the subsurface from measurements of electrical potential caused by electrical currents injected into an array of electrodes in the subsurface. By use of current injection and potential measurement electrodes to generate data about the subsurface resistivity distribution, which data is then used in an inverse calculation, a model of the electrical resistivity distribution can be obtained. The inverse model may be constrained by independent data to better define an inverse solution. The method utilizes pairs of electrically conductive (steel) borehole casings as current injection electrodes and as potential measurement electrodes. The greater the number of steel cased boreholes in an array, the greater the amount of data is obtained. The steel cased boreholes may be utilized for either current injection or potential measurement electrodes. The subsurface model produced by this method can be 2 or 3 dimensional in resistivity depending on the detail desired in the calculated resistivity distribution and the amount of data to constrain the models. 2 figs.

  1. Compressed sensing quantum process tomography for superconducting quantum gates

    E-Print Network [OSTI]

    Andrey V. Rodionov; Andrzej Veitia; R. Barends; J. Kelly; Daniel Sank; J. Wenner; John M. Martinis; Robert L. Kosut; Alexander N. Korotkov

    2014-07-03T23:59:59.000Z

    We apply the method of compressed sensing (CS) quantum process tomography (QPT) to characterize quantum gates based on superconducting Xmon and phase qubits. Using experimental data for a two-qubit controlled-Z gate, we obtain an estimate for the process matrix $\\chi$ with reasonably high fidelity compared to full QPT, but using a significantly reduced set of initial states and measurement configurations. We show that the CS method still works when the amount of used data is so small that the standard QPT would have an underdetermined system of equations. We also apply the CS method to the analysis of the three-qubit Toffoli gate with numerically added noise, and similarly show that the method works well for a substantially reduced set of data. For the CS calculations we use two different bases in which the process matrix $\\chi$ is approximately sparse, and show that the resulting estimates of the process matrices match each ther with reasonably high fidelity. For both two-qubit and three-qubit gates, we characterize the quantum process by not only its process matrix and fidelity, but also by the corresponding standard deviation, defined via variation of the state fidelity for different initial states.

  2. Pretreatment Staging Positron Emission Tomography/Computed Tomography in Patients With Inflammatory Breast Cancer Influences Radiation Treatment Field Designs

    SciTech Connect (OSTI)

    Walker, Gary V. [Department of Radiation Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Niikura, Naoki [Department of Breast and Endocrine Surgery, Tokai University School of Medicine, Kanagawa (Japan)] [Department of Breast and Endocrine Surgery, Tokai University School of Medicine, Kanagawa (Japan); Yang Wei [Department of Diagnostic Radiology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Diagnostic Radiology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Rohren, Eric [Department of Nuclear Medicine, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Nuclear Medicine, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Valero, Vicente [Department of Breast Medical Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Breast Medical Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Woodward, Wendy A. [Department of Radiation Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Alvarez, Ricardo H. [Department of Breast Medical Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Breast Medical Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Lucci, Anthony [Department of Surgical Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Surgical Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Ueno, Naoto T. [Department of Breast Medical Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Breast Medical Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Buchholz, Thomas A., E-mail: tbuchhol@mdanderson.org [Department of Radiation Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2012-08-01T23:59:59.000Z

    Purpose: Positron emission tomography/computed tomography (PET/CT) is increasingly being utilized for staging of inflammatory breast cancer (IBC). The purpose of this study was to define how pretreatment PET/CT studies affected postmastectomy radiation treatment (PMRT) planning decisions for IBC. Methods and Materials: We performed a retrospective analysis of 62 patients diagnosed with IBC between 2004 and 2009, who were treated with PMRT in our institution and who had a staging PET/CT within 3 months of diagnosis. Patients received a baseline physical examination, staging mammography, ultrasonographic examination of breast and draining lymphatics, and chest radiography; most patients also had a bone scan (55 patients), liver imaging (52 patients), breast MRI (46 patients), and chest CT (25 patients). We compared how PET/CT findings affected PMRT, assuming that standard PMRT would target the chest wall, level III axilla, supraclavicular fossa, and internal mammary chain (IMC). Any modification of target volumes, field borders, or dose prescriptions was considered a change. Results: PET/CT detected new areas of disease in 27 of the 62 patients (44%). The areas of additional disease included the breast (1 patient), ipsilateral axilla (1 patient), ipsilateral supraclavicular (4 patients), ipsilateral infraclavicular (1 patient), ipsilateral IMC (5 patients), ipsilateral subpectoral (3 patients), mediastinal (8 patients), other distant/contralateral lymph nodes (15 patients), or bone (6 patients). One patient was found to have a non-breast second primary tumor. The findings of the PET/CT led to changes in PMRT in 11 of 62 patients (17.7%). These changes included additional fields in 5 patients, adjustment of fields in 2 patients, and higher doses to the supraclavicular fossa (2 patients) and IMC (5 patients). Conclusions: For patients with newly diagnosed IBC, pretreatment PET/CT provides important information concerning involvement of locoregional lymph nodes, mediastinal lymph nodes, and unsuspected sites of distant metastasis. This information is important in the design of radiotherapy treatment fields and, therefore, we recommend that PET/CT be a component of initial staging for IBC.

  3. X-ray Computed Tomography of coal: Final report

    SciTech Connect (OSTI)

    Maylotte, D.H.; Spiro, C.L.; Kosky, P.G.; Lamby, E.J.

    1986-12-01T23:59:59.000Z

    X-ray Computed Tomography (CT) is a method of mapping with x-rays the internal structures of coal. The technique normally produces 2-D images of the internal structures of an object. These images can be recast to create pseudo 3-D representations. CT of coal has been explored for a variety of different applications to coal and coal processing technology. In a comparison of CT data with conventional coal analyses and petrography, CT was found to offer a good indication of the total ash content of the coal. The spatial distribution of the coal mineral matter as seen with CT has been suggested as an indicator of coal washability. Studies of gas flow through coal using xenon gas as a tracer have shown the extremely complicated nature of the modes of penetration of gas through coal, with significant differences in the rates at which the gas can pass along and across the bedding planes of coal. In a special furnace designed to allow CT images to be taken while the coal was being heated, the pyrolysis and gasification of coal have been studied. Gasification rates with steam and CO/sub 2/ for a range of coal ranks have been obtained, and the location of the gasification reactions within the piece of coal can be seen. Coal drying and the progress of the pyrolysis wave into coal have been examined when the coal was subjected to the kind of sudden temperature jump that it might experience in fixed bed gasifier applications. CT has also been used to examine stable flow structures within model fluidized beds and the accessibility of lump coal to microbial desulfurization. 53 refs., 242 figs., 26 tabs.

  4. Factors Affecting Prostate Volume Estimation in Computed Tomography Images

    SciTech Connect (OSTI)

    Yang, Cheng-Hsiu [Department of Power Mechanical Engineering, National Tsing Hua University, Hsinchu, Taiwan (China); Wang, Shyh-Jen [Divisions of Experimental Surgery, Department of Surgery, Taipei Veterans General Hospital, Taipei, Taiwan (China); Institute of Biomedical Engineering, National Yang Ming University, Taipei, Taiwan (China); Lin, Alex Tong-Long [Divisions of Urology, Department of Surgery, Taipei Veterans General Hospital, Taipei, Taiwan (China); Lin, Chao-An, E-mail: calin@pme.nthu.edu.t [Department of Power Mechanical Engineering, National Tsing Hua University, Hsinchu, Taiwan (China)

    2011-04-01T23:59:59.000Z

    The aim of this study was to investigate how apex-localizing methods and the computed tomography (CT) slice thickness affected the CT-based prostate volume estimation. Twenty-eight volunteers underwent evaluations of prostate volume by CT, where the contour segmentations were performed by three observers. The bottom of ischial tuberosities (ITs) and the bulb of the penis were used as reference positions to locate the apex, and the distances to the apex were recorded as 1.3 and 2.0 cm, respectively. Interobserver variations to locate ITs and the bulb of the penis were, on average, 0.10 cm (range 0.03-0.38 cm) and 0.30 cm (range 0.00-0.98 cm), respectively. The range of CT slice thickness varied from 0.08-0.48 cm and was adopted to examine the influence of the variation on volume estimation. The volume deviation from the reference case (0.08 cm), which increases in tandem with the slice thickness, was within {+-} 3 cm{sup 3}, regardless of the adopted apex-locating reference positions. In addition, the maximum error of apex identification was 1.5 times of slice thickness. Finally, based on the precise CT films and the methods of apex identification, there were strong positive correlation coefficients for the estimated prostate volume by CT and the transabdominal ultrasonography, as found in the present study (r > 0.87; p < 0.0001), and this was confirmed by Bland-Altman analysis. These results will help to identify factors that affect prostate volume calculation and to contribute to the improved estimation of the prostate volume based on CT images.

  5. Simulation et analyse par tomographie X de la dformation l'chelle msoscopique de renforts textiles de composites en cours de mise en forme

    E-Print Network [OSTI]

    Boyer, Edmond

    like permeability evaluations. A mechanical analysis of the reinforcement at meso-scale is proposed mésoscopique, Hypo-élasticité, Tomographie Keywords : Composite Forming, Finite Element, X-Ray tomography, Meso-scale

  6. Positron Emission Tomography/Computed Tomography-Guided Intensity-Modulated Radiotherapy for Limited-Stage Small-Cell Lung Cancer

    SciTech Connect (OSTI)

    Shirvani, Shervin M.; Komaki, Ritsuko [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Heymach, John V.; Fossella, Frank V. [Department of Thoracic/Head and Neck Medical Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Chang, Joe Y., E-mail: jychang@mdanderson.org [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States)

    2012-01-01T23:59:59.000Z

    Purpose: Omitting elective nodal irradiation from planning target volumes does not compromise outcomes in patients with non-small-cell lung cancer, but whether the same is true for those with limited-stage small-cell lung cancer (LS-SCLC) is unknown. Therefore, in the present study, we sought to determine the clinical outcomes and the frequency of elective nodal failure in patients with LS-SCLC staged using positron emission tomography/computed tomography and treated with involved-field intensity-modulated radiotherapy. Methods and Materials: Between 2005 and 2008, 60 patients with LS-SCLC at our institution underwent disease staging using positron emission tomography/computed tomography before treatment using an intensity-modulated radiotherapy plan in which elective nodal irradiation was intentionally omitted from the planning target volume (mode and median dose, 45 Gy in 30 fractions; range, 40.5 Gy in 27 fractions to 63.8 Gy in 35 fractions). In most cases, concurrent platinum-based chemotherapy was administered. We retrospectively reviewed the clinical outcomes to determine the overall survival, relapse-free survival, and failure patterns. Elective nodal failure was defined as recurrence in initially uninvolved hilar, mediastinal, or supraclavicular nodes. Survival was assessed using the Kaplan-Meier method. Results: The median age of the study patients at diagnosis was 63 years (range, 39-86). The median follow-up duration was 21 months (range, 4-58) in all patients and 26 months (range, 4-58) in the survivors. The 2-year actuarial overall survival and relapse-free survival rate were 58% and 43%, respectively. Of the 30 patients with recurrence, 23 had metastatic disease and 7 had locoregional failure. We observed only one isolated elective nodal failure. Conclusions: To our knowledge, this is the first study to examine the outcomes in patients with LS-SCLC staged with positron emission tomography/computed tomography and treated with definitive intensity-modulated radiotherapy. In these patients, elective nodal irradiation can be safely omitted from the planning target volume for the purposes of dose escalation and toxicity reduction.

  7. Application of stochastic Galerkin FEM to the complete electrode model of electrical impedance tomography

    SciTech Connect (OSTI)

    Leinonen, Matti, E-mail: matti.leinonen@aalto.fi; Hakula, Harri, E-mail: harri.hakula@aalto.fi; Hyvönen, Nuutti, E-mail: nuutti.hyvonen@aalto.fi

    2014-07-15T23:59:59.000Z

    The aim of electrical impedance tomography is to determine the internal conductivity distribution of some physical body from boundary measurements of current and voltage. The most accurate forward model for impedance tomography is the complete electrode model, which consists of the conductivity equation coupled with boundary conditions that take into account the electrode shapes and the contact resistances at the corresponding interfaces. If the reconstruction task of impedance tomography is recast as a Bayesian inference problem, it is essential to be able to solve the complete electrode model forward problem with the conductivity and the contact resistances treated as a random field and random variables, respectively. In this work, we apply a stochastic Galerkin finite element method to the ensuing elliptic stochastic boundary value problem and compare the results with Monte Carlo simulations.

  8. FIB–SEM tomography of 4th generation PWA 1497 superalloy

    SciTech Connect (OSTI)

    Zi?tara, Maciej, E-mail: zietara@agh.edu.pl; Kruk, Adam, E-mail: kruczek@agh.edu.pl; Gruszczy?ski, Adam, E-mail: gruszcz@agh.edu.pl; Czyrska-Filemonowicz, Aleksandra, E-mail: czyrska@agh.edu.pl

    2014-01-15T23:59:59.000Z

    The effect of creep deformation on the microstructure of the PWA 1497 single crystal Ni-base superalloy developed for turbine blade applications was investigated. The aim of the present study was to characterize quantitatively a superalloy microstructure and subsequent development of rafted ?? precipitates in the PWA 1497 during creep deformation at 982 °C and 248 MPa up to rupture. The PWA1497 microstructure was characterized by scanning electron microscopy and FIB–SEM electron tomography. The 3D reconstruction of the PWA1497 microstructure is presented and discussed. - Highlights: • The microstructure of PWA1497 superalloy was examined using FIB–SEM tomography. • In case of modern single crystal superalloys, measurements of A{sub A} are adequate for V{sub V}. • During creep the ? channel width increases from 65 to 193 nm for ruptured specimen. • Tomography is a useful technique for quantitative studies of material microstructure.

  9. Three-dimensional morphology of cementite in steel studied by X-ray phase-contrast tomography

    E-Print Network [OSTI]

    Stallinga, Sjoerd

    Three-dimensional morphology of cementite in steel studied by X-ray phase-contrast tomography-destructive, in-line X-ray phase-contrast tomography (PCT) can be used to study the three-dimensional mor- phology- and cold-forming operations of the steel. Studying the evolution of the morphology of cement- ite in 3-D

  10. SNR-weighted Sinogram Smoothing with Improved Noise-resolution Properties for Low-dose X-ray Computed Tomography

    E-Print Network [OSTI]

    -ray Computed Tomography T. Li*a , J. Wanga , J. Wena , X. Lib , H. Luc , J. Hsiehd , and Z. Lianga a State-beam, uniform attenuation, resolution variation. 1. INTRODUCTION It is well known that the quality of computed tomography (CT) images would be severely degraded by the excessive quantum noise under extremely low x

  11. Relation between Optical Fresnel transformation and quantum tomography in two-mode entangled case

    E-Print Network [OSTI]

    Hong-yi Fan; Li-yun Hu

    2009-11-09T23:59:59.000Z

    Similar in spirit to the preceding work [Opt. Commun. 282 (2009) 3734] where the relation between optical Fresnel transformation and quantum tomography is revealed, we study this kind of relationship in the two-mode entangled case. We show that under the two-mode Fresnel transformation the bipartite entangled state density |eta>_{r,s}Fresnel operator in quantum optics, and s,r are the complex-value expression of (A, B, C,D). So the probability distribution for the Fresnel quadrature phase is the {tomography (Radon transform of the two-mode Wigner function), correspondingly, {s,r}_=. Similarly, we find a simial conclusion in the `frequency` domain.

  12. Multi-Resolution Seismic Tomography Based on Recursive Tessellation Hierarchy

    SciTech Connect (OSTI)

    Simmons, N A; Myers, S C; Ramirez, A

    2009-07-01T23:59:59.000Z

    A 3-D global tomographic model that reconstructs velocity structure at multiple scales and incorporates laterally variable seismic discontinuities is currently being developed. The model parameterization is node-based where nodes are placed along vertices defined by triangular tessellations of a spheroidal surface. The triangular tessellation framework is hierarchical. Starting with a tetrahexahedron representing the whole globe (1st level of the hierarchy, 24 faces), they divide each triangle of the tessellation into daughter triangles. The collection of all daughter triangles comprises the 2nd level of the tessellation hierarchy and further recursion produces an arbitrary number of tessellation levels and arbitrarily fine node-spacing. They have developed an inversion procedure that takes advantage of the recursive properties of the tessellation hierarchies by progressively solving for shorter wavelength heterogeneities. In this procedure, we first perform the tomographic inversion using a tessellation level with coarse node spacing. They find that a coarse node spacing of approximately 8{sup o} is adequate to capture bulk regional properties. They then conduct the tomographic inversion on a 4{sup o} tessellation level using the residuals and inversion results from the 8{sup o} run. In practice they find that the progressive tomography approach is robust, providing an intrinsic regularization for inversion stability and avoids the issue of predefining resolution levels. Further, determining average regional properties with coarser tessellation levels enables long-wavelength heterogeneities to account for sparsely sampled regions (or regions of the mantle where longer wavelength patterns of heterogeneity suffice) while allowing shorter length-scale heterogeneities to emerge where necessary. They demonstrate the inversion approach with a set of synthetic test cases that mimic the complex nature of data arrangements (mixed-determined inversion) common to most tomographic problems. They also apply the progressive inversion approach with Pn waves traveling within the Middle East region and compare the results to simple tomographic inversions. As expected from synthetic testing, the progressive approach results in detailed structure where there is high data density and broader regional anomalies where seismic information is sparse. The ultimate goal is to use these methods to produce a seamless, multi-resolution global tomographic model with local model resolution determined by the constraints afforded by available data. They envisage this new technique as the general approach to be employed for future multi-resolution model development with complex arrangements of regional and teleseismic information.

  13. Improved proton computed tomography by dual modality image reconstruction

    SciTech Connect (OSTI)

    Hansen, David C., E-mail: dch@ki.au.dk; Bassler, Niels [Experimental Clinical Oncology, Aarhus University, 8000 Aarhus C (Denmark)] [Experimental Clinical Oncology, Aarhus University, 8000 Aarhus C (Denmark); Petersen, Jřrgen Breede Baltzer [Medical Physics, Aarhus University Hospital, 8000 Aarhus C (Denmark)] [Medical Physics, Aarhus University Hospital, 8000 Aarhus C (Denmark); Sřrensen, Thomas Sangild [Computer Science, Aarhus University, 8000 Aarhus C, Denmark and Clinical Medicine, Aarhus University, 8200 Aarhus N (Denmark)] [Computer Science, Aarhus University, 8000 Aarhus C, Denmark and Clinical Medicine, Aarhus University, 8200 Aarhus N (Denmark)

    2014-03-15T23:59:59.000Z

    Purpose: Proton computed tomography (CT) is a promising image modality for improving the stopping power estimates and dose calculations for particle therapy. However, the finite range of about 33 cm of water of most commercial proton therapy systems limits the sites that can be scanned from a full 360° rotation. In this paper the authors propose a method to overcome the problem using a dual modality reconstruction (DMR) combining the proton data with a cone-beam x-ray prior. Methods: A Catphan 600 phantom was scanned using a cone beam x-ray CT scanner. A digital replica of the phantom was created in the Monte Carlo code Geant4 and a 360° proton CT scan was simulated, storing the entrance and exit position and momentum vector of every proton. Proton CT images were reconstructed using a varying number of angles from the scan. The proton CT images were reconstructed using a constrained nonlinear conjugate gradient algorithm, minimizing total variation and the x-ray CT prior while remaining consistent with the proton projection data. The proton histories were reconstructed along curved cubic-spline paths. Results: The spatial resolution of the cone beam CT prior was retained for the fully sampled case and the 90° interval case, with the MTF = 0.5 (modulation transfer function) ranging from 5.22 to 5.65?linepairs/cm. In the 45° interval case, the MTF = 0.5 dropped to 3.91?linepairs/cm For the fully sampled DMR, the maximal root mean square (RMS) error was 0.006 in units of relative stopping power. For the limited angle cases the maximal RMS error was 0.18, an almost five-fold improvement over the cone beam CT estimate. Conclusions: Dual modality reconstruction yields the high spatial resolution of cone beam x-ray CT while maintaining the improved stopping power estimation of proton CT. In the case of limited angles, the use of prior image proton CT greatly improves the resolution and stopping power estimate, but does not fully achieve the quality of a 360° proton CT scan.

  14. To cite this document: Haine, Ghislain An observer-based approach for thermoacoustic tomography. (2014) In: The 21st International Symposium on Mathematical Theory of

    E-Print Network [OSTI]

    Mailhes, Corinne

    2014-01-01T23:59:59.000Z

    To cite this document: Haine, Ghislain An observer-based approach for thermoacoustic tomography administrator: staff-oatao@inp-toulouse.fr #12;An observer-based approach for thermoacoustic tomography Ghislain will consider in this paper, the algorithm studied in [29]. In thermoacoustic tomography, the problem

  15. To cite this document: Haine, Ghislain Solving Thermoacoustic Tomography with an observer-based algorithm. (2014) In: Journes Ondes du Sud-Ouest, 05 February 2014 -

    E-Print Network [OSTI]

    Mailhes, Corinne

    2014-01-01T23:59:59.000Z

    To cite this document: Haine, Ghislain Solving Thermoacoustic Tomography with an observer-oatao@inp-toulouse.fr #12;Solving Thermoacoustic Tomography with an observer-based algorithm Ghislain Haine Department] and finally, the one we will consider, the algorithm studied in [20]. In thermoacoustic tomography

  16. Dose uncertainty due to computed tomography ,,CT... slice thickness in CT-based high dose rate brachytherapy of the prostate cancer

    E-Print Network [OSTI]

    Pouliot, Jean

    Dose uncertainty due to computed tomography ,,CT... slice thickness in CT-based high dose rate in Medicine. DOI: 10.1118/1.1785454 Key words: high dose rate brachytherapy, computed tomography, prostate at risk OARs by providing three-dimensional 3D anatomical information from computed tomography CT

  17. The influence of glass fibers on elongational viscosity studied by means of optical coherence tomography and X-ray computed tomography

    SciTech Connect (OSTI)

    Aigner, M., E-mail: michael.aigner@jku.at; Köpplmayr, T., E-mail: thomas.koepplmayr@jku.at, E-mail: Christian.lang@jku.at; Lang, C., E-mail: thomas.koepplmayr@jku.at, E-mail: Christian.lang@jku.at; Burzic, I., E-mail: ivana.burzic@jku.at, E-mail: juergen.miethlinger@jku.at; Miethlinger, J., E-mail: ivana.burzic@jku.at, E-mail: juergen.miethlinger@jku.at [Institute of Polymer Extrusion and Compounding, Johannes Kepler University Linz (Austria); Salaberger, D., E-mail: dietmar.salaberger@fh-wels.at [University of Applied Sciences Upper Austria (Austria); Buchsbaum, A., E-mail: andreas.buchsbaum@recendt.at; Leitner, M. [Research Center for Non Destructive Testing GmbH (Austria); Heise, B., E-mail: bettina.heise@jku.at [Christian Doppler Laboratory for Microscopic and Spectroscopic Material Characterization, ZONA, Austria and Institute for Knowledge-based Mathematical Systems, Johannes Kepler University Linz (Austria); Schausberger, S. E., E-mail: stefan.schausberger@jku.at; Stifter, D. [Christian Doppler Laboratory for Microscopic and Spectroscopic Material Characterization, ZONA (Austria)

    2014-05-15T23:59:59.000Z

    We report on the flow characteristics of glass-fiber-reinforced polymers in elongational rheometry. Unlike polymers with geometrically isotropic fillers, glass-fiber-reinforced polymers exhibit flow behavior and rheology that depend heavily on the orientation, the length distribution and the content of the fibers. One of the primary objectives of this study was to determine the effect of fiber orientation, concentration and distribution on the entrance pressure drop by means of optical coherence tomography (OCT), full-field optical coherence microscopy (FF-OCM), and X-ray computed tomography (X-CT). Both pressure drop and melt flow were analyzed using a special elongation die (Thermo Scientific X-Die [3]) for inline measurements. Samples with a variety of fiber volume fractions, fiber lengths and processing temperatures were measured.

  18. Large-Scale Fabrication, 3D Tomography, and Lithium-Ion Battery Application of Porous Silicon

    E-Print Network [OSTI]

    Zhou, Chongwu

    Large-Scale Fabrication, 3D Tomography, and Lithium-Ion Battery Application of Porous Silicon, United States *S Supporting Information ABSTRACT: Recently, silicon-based lithium-ion battery anodes have for the next-generation lithium-ion batteries with enhanced capacity and energy density. KEYWORDS: Cost

  19. Degradation of Li/S Battery Electrodes Studied Using X-ray Phase Contrast Tomography

    E-Print Network [OSTI]

    Schmidt, Volker

    in lithium-ion battery systems. This technology is thus drawing attention from academic and industrial researchers intensively studied rechargeable lithium-ion batteries, since the energy demand of electric1 Degradation of Li/S Battery Electrodes Studied Using X-ray Phase Contrast Tomography L. Zielkea

  20. Computerized Tomography and its Applications: a Guided Tour \\Lambda J.B.T.M. Roerdink

    E-Print Network [OSTI]

    Roerdink, Jos B.T.M.

    ­rays, gamma rays, visible light, electrons or neutrons to ultrasound waves or nuclear magnetic resonance projections', i.e. the recovery of a function from its line or (hyper)plane integrals (from the Greek ř ' o). In contrast with this stands emission computerized tomography (ECT), where the probe, such as a radioactive

  1. Eddy Current Tomography Using a Binary Markov Mila Nikolova and Ali MohammadDjafari

    E-Print Network [OSTI]

    Nikolova, Mila

    Eddy Current Tomography Using a Binary Markov Model Mila Nikolova and Ali Mohammad and notches. The medium is illuminated with a monochromatic electric field; the anomalies induce eddy currents in various fields such as nuclear power plants and aerospace engineering. 1 #12; The objective of eddy

  2. 4D Computed Tomography Reconstruction from Few-Projection Data via Temporal Non-local

    E-Print Network [OSTI]

    Zakharov, Vladimir

    4D Computed Tomography Reconstruction from Few-Projection Data via Temporal Non, University of California, Los Angeles, Los Angeles, CA 90095-1555, USA 3 Department of Mathematics be reconstructed simultaneously based on extremely under-sampled x-ray projections. Our algorithm is validated

  3. Optical Coherence Tomography Scan Circle Location and Mean Retinal Nerve Fiber Layer

    E-Print Network [OSTI]

    Srinivasan, Vivek J.

    Optical Coherence Tomography Scan Circle Location and Mean Retinal Nerve Fiber Layer Measurement) retinal nerve fiber layer (RNFL) thickness mea- surements of varying the standard 3.4-mm-diameter circle of the variable circle placement effect. RNFL thickness was measured on this three-dimensional dataset by using

  4. Diffuse Optical Tomography of Cerebral Blood Flow, Oxygenation, and Metabolism in Rat During Focal Ischemia

    E-Print Network [OSTI]

    Yodh, Arjun G.

    of oxygen consumption (CMRO2). Temporary (60-minute) MCAO was performed on five rats. Ischemic changes--Cerebral metabolic rate of oxygen consumption. Diffuse optical tomography (DOT) of the brain is an attractive new complementary to those of magnetic resonance imaging (MRI) and positron emission tomog- raphy (PET), and holds

  5. Manual-scanning optical coherence tomography probe based on position tracking

    E-Print Network [OSTI]

    Yang, Changhuei

    Manual-scanning optical coherence tomography probe based on position tracking Jian Ren,1, * Jigang to reconstruct images for a manual-scanning optical coherence tomog- raphy (OCT) probe is proposed's pose. The continuous device poses tracking, and the collected OCT depth scans can then be combined

  6. Nondestructive evaluation of Polymer Coating Structures on Pharmaceutical Pellets using Full Field Optical Coherence Tomography

    E-Print Network [OSTI]

    Li, C; Zeitler, J. A; Dong, Y; Shen, Y.-C

    Full field optical coherence tomography (FF-OCT) using a conventional LED light source and a CMOS camera has been developed for characterising coatings on small pellet samples. A set of en-face images covering an area of 700µm x 700µm were taken...

  7. Use of Physical Models to Facilitate Transfer of Physics Learning to Understand Positron Emission Tomography*

    E-Print Network [OSTI]

    Zollman, Dean

    interactive learning with the aid of physical models. Three different types of non-scaffolded transfer haveUse of Physical Models to Facilitate Transfer of Physics Learning to Understand Positron Emission, positron emission tomography, transfer of learning PACS: 01.40Fk Supported by the National Science

  8. Conventional and 360 degree electron tomography of a micro-crystalline silicon solar cell

    E-Print Network [OSTI]

    Dunin-Borkowski, Rafal E.

    for use as the active absorber layer in low cost solar cells [1], for which efficiencies higher than 8Conventional and 360 degree electron tomography of a micro- crystalline silicon solar cell M thereafter) in micro-crystalline silicon (µc-Si:H) solar cell. The limitations of inferring the 3D geometry

  9. Post-doc GIPSA-Lab / LGIT : Ocean Acoustic Tomography in shallow water and Signal Processing

    E-Print Network [OSTI]

    van Tiggelen, Bart

    Post-doc GIPSA-Lab / LGIT : Ocean Acoustic Tomography in shallow water and Signal Processing influence and pollution in coastal areas. Consequently, they need the precise knowledge of the spatial and to estimate the sur- face height is also very interesting as these problems have many applications (acoustic

  10. Jet tomography of AA-collisions at RHIC and LHC energies

    E-Print Network [OSTI]

    Zakharov, B G

    2013-01-01T23:59:59.000Z

    We present our recent results on jet tomography of AA-collisions at RHIC and LHC. We focus on flavor dependence of the nuclear modification factor. The computations are performed accounting for radiative and collisional parton energy loss with running coupling constant.

  11. A Hard X-ray KB-FZP Microscope for Tomography with Sub-100-nm Resolution

    E-Print Network [OSTI]

    Braun, Paul

    Bielefeld, Germany, 7 BESSY GmbH, Albert-Einstein-Str.15, 12489 Berlin, Germany 8 Department of Physics. INTRODUCTION Synchrotron-based hard X-ray tomography is nowadays a standard technique for structural analyses sciences, biomedicine, planetary science etc.. The high coherence of third generation synchrotron sources

  12. Uniqueness of reconstruction and an inversion procedure for thermoacoustic and photoacoustic tomography

    E-Print Network [OSTI]

    Mark Agranovsky; Peter Kuchment

    2007-06-05T23:59:59.000Z

    The paper contains a simple approach to reconstruction in Thermoacoustic and Photoacoustic Tomography. The technique works for any geometry of point detectors placement and for variable sound speed satisfying a non-trapping condition. A uniqueness of reconstruction result is also obtained.

  13. A Uniqueness Theorem for Thermoacoustic Tomography in the Case of Limited Boundary Data

    E-Print Network [OSTI]

    Steinhauer, Dustin

    2009-01-01T23:59:59.000Z

    We prove a uniqueness theorem for compactly supported initial data for the variable speed wave equation arising in models of thermoacoustic tomography, given measurements on a part of the boundary. The proof is based on domain of dependence arguments and D. Tataru's unique continuation theorem.

  14. Uniqueness of reconstruction and an inversion procedure for thermoacoustic and photoacoustic tomography

    E-Print Network [OSTI]

    Agranovsky, Mark

    2007-01-01T23:59:59.000Z

    The paper contains a simple approach to reconstruction in Thermoacoustic and Photoacoustic Tomography. The technique works for any geometry of point detectors placement and for variable sound speed satisfying a non-trapping condition. A uniqueness of reconstruction result is also obtained.

  15. A Reconstruction Procedure for Thermoacoustic Tomography in the Case of Limited Boundary Data

    E-Print Network [OSTI]

    Steinhauer, Dustin

    2009-01-01T23:59:59.000Z

    We derive an explicit method for reconstructing singularities of the initial data in a thermoacoustic tomography problem, in the case of variable sound speed and limited boundary data. In order to obtain this explicit formula we assume the metric induced by the sound speed does not have conjugate points inside the region to be observed.

  16. On reconstruction formulas and algorithms for the thermoacoustic and photoacoustic tomography

    E-Print Network [OSTI]

    Agranovsky, M; Kunyansky, L

    2007-01-01T23:59:59.000Z

    The paper surveys recent progress in establishing uniqueness and developing inversion formulas and algorithms for the thermoacoustic tomography. In mathematical terms, one deals with a rather special inverse problem for the wave equation. In the case of constant sound speed, it can also be interpreted as a problem concerning the spherical mean transform.

  17. Noninvasive Monitoring of Local Drug Release Using X-ray Computed Tomography: Optimization and

    E-Print Network [OSTI]

    Gao, Jinming

    -performanceliquidchromatography(HPLC), high resolution mass spectrometry, or atomic absorption spectrometry (AAS). These procedures,3 Gamma-emission imaging, positron- emission tomography (PET), and magnetic reso- nance imaging (MRI of these methods are rela- tively low spatial resolution (5 and 10 mm for clinical gamma imaging and PET

  18. Cross gender-age trabecular texture analysis in cone beam computed tomography

    E-Print Network [OSTI]

    Ling, Haibin

    osteoporosis screening tools in the jaws. Keywords: cone-beam computed tomography, osteoporosis, radiology, osteoporosis afflicts 55% of Americans aged 50 and above.1 Early diagnosis of osteoporosis is very important to prevent more serious complications such as hip fracture. The current gold standard for osteoporosis

  19. An Efficient Approach for Optical Radiative Transfer Tomography using the Spherical Harmonics Discrete Ordinates Method

    E-Print Network [OSTI]

    Levis, Aviad; Aides, Amit; Davis, Anthony B

    2015-01-01T23:59:59.000Z

    This paper introduces a method to preform optical tomography, using 3D radiative transfer as the forward model. We use an iterative approach predicated on the Spherical Harmonics Discrete Ordinates Method (SHDOM) to solve the optimization problem in a scalable manner. We illustrate with an application in remote sensing of a cloudy atmosphere.

  20. Development of a proton Computed Tomography (pCT) scanner at NIU

    E-Print Network [OSTI]

    Uzunyan, S A; Boi, S; Coutrakon, G; Dyshkant, A; Erdelyi, B; Gearhart, A; Hedin, D; Johnson, E; Krider, J; Zutshi, V; Ford, R; Fitzpatrick, T; Sellberg, G; Rauch, J E; Roman, M; Rubinov, P; Wilson, P; Lalwani, K; Naimuddin, M

    2013-01-01T23:59:59.000Z

    We describe the development of a proton Computed Tomography (pCT) scanner at Northern Illinois University (NIU) in collaboration with Fermilab and Delhi University. This paper provides an overview of major components of the scanner and a detailed description of the data acquisition system (DAQ).

  1. Detection of screw threads in computed tomography 3D density fields

    E-Print Network [OSTI]

    Kosarevsky, Sergey

    2013-01-01T23:59:59.000Z

    In this paper, a new method is proposed to automatically detect screw threads in 3D density fields obtained from computed tomography measurement devices. The described method can be used to automate many operations during screw thread inspection process and drastically reduce operator's influence on the measurement process resulting in lower measurement times and increased repeatability.

  2. Development of a proton Computed Tomography (pCT) scanner at NIU

    E-Print Network [OSTI]

    S. A. Uzunyan; G. Blazey; S. Boi; G. Coutrakon; A. Dyshkant; B. Erdelyi; A. Gearhart; D. Hedin; E. Johnson; J. Krider; V. Zutshi; R. Ford; T. Fitzpatrick; G. Sellberg; J. E. Rauch; M. Roman; P. Rubinov; P. Wilson; K. Lalwani; M. Naimuddin

    2013-12-13T23:59:59.000Z

    We describe the development of a proton Computed Tomography (pCT) scanner at Northern Illinois University (NIU) in collaboration with Fermilab and Delhi University. This paper provides an overview of major components of the scanner and a detailed description of the data acquisition system (DAQ).

  3. Fresnel tomography: a novel approach to the wave function reconstruction based on Fresnel representation of tomograms

    E-Print Network [OSTI]

    S. De Nicola; R. Fedele; M. A. Man'ko; V. I. Man'ko

    2005-03-03T23:59:59.000Z

    New type of tomographic probability distribution, which contains complete information on the density matrix (wave function) related to the Fresnel transform of the complex wave function, is introduced. Relation to symplectic tomographic probability distribution is elucidated. Multimode generalization of the Fresnel tomography is presented. Examples of applications of the present approach are given.

  4. Figure 5 : Inversed attenuation tomography The Fresnel volume thus defined, also called Frchet kernel

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Figure 5 : Inversed attenuation tomography The Fresnel volume thus defined, also called Fréchet system with the LSQR algorithm : Because the size of the Fresnel volume thus defined is dependent propose to compute the Fresnel weights for a monochromatic wave, increasing its frequency at each step

  5. XEDS STEM Tomography For 3D Chemical Characterization Of Nanoscale Particles

    SciTech Connect (OSTI)

    Genc, Arda; Kovarik, Libor; Gu, Meng; Cheng, Huikai; Plachinda, Pavel; Pullan, Lee; Freitag, Bert; Wang, Chong M.

    2013-08-01T23:59:59.000Z

    We present a tomography technique which couples scanning transmission electron microscopy (STEM) and X-ray energy dispersive spectrometry (XEDS) to resolve 3D distribution of elements in nanoscale materials. STEM imaging when combined with a symmetrically arranged XEDS detector design around the specimen overcomes many of the obstacles in 3D spectroscopic tomography of nanoscale materials and successfully elucidate the 3D chemical information in a large field of view of the TEM sample. We employed this technique to investigate 3D distribution of Nickel (Ni), Manganese (Mn) and Oxygen (O) in Li(NiMn)O2 battery cathode material. For this purpose, 2D elemental maps were acquired for a range of tilt angles and reconstructed to obtain 3D elemental distribution in an isolated Li(NiMnO2) nanoparticle. The results highlight the strength of this technique in 3D chemical analysis of nanoscale materials by successfully resolving Ni, Mn and O elemental distributions in 3D and discovering the new phenomenon of Ni surface segregation in this material. Furthermore, the comparison of simultaneously acquired HAADF STEM and XEDS STEM tomography results show that XEDS STEM tomography provides additional 3D chemical information of the material especially when there is low atomic number (Z) contrast in the material of interest.

  6. Effect on Lesion Detectability of Proximity to Anatomical Boundaries in Emission Tomography

    E-Print Network [OSTI]

    into the ET recon- struction. The increasing availability of PET-CT and SPECT- CT has engendered renewed of (idealized) lesion boundaries did indeed lead to enhanced detectability. To complicate matters, a PET-CT. Kulkarni, P. Khurd, I. Hsiao and G. Gindi Abstract-- In emission tomography (ET) comprising PET and SPECT

  7. VIDEO IDENTIFICATION USING VIDEO TOMOGRAPHY Gustavo Leon, Hari Kalva, and Borko Furht

    E-Print Network [OSTI]

    Kalva, Hari

    VIDEO IDENTIFICATION USING VIDEO TOMOGRAPHY Gustavo Leon, Hari Kalva, and Borko Furht Department of Computer Science and Engineering, Florida Atlantic University, Boca Raton, FL, USA ABSTRACT Video popularity of online video services. The problem addressed in this paper is the identification of a given

  8. Evidence from threedimensional seismic tomography for a substantial accumulation of gas hydrate in a fluidescape

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Evidence from threedimensional seismic tomography for a substantial accumulation of gas hydrate to be associated with the emplacement of hydrate, accompanying the invasion of the gas hydrate stability zone accumulation of gas hydrate in a fluidescape chimney in the Nyegga pockmark field, offshore Norway, J. Geophys

  9. Algorithms for Fluorescence Lifetime Microscopy and Optical Coherence Tomography Data Analysis: Applications for Diagnosis of Atherosclerosis and Oral Cancer

    E-Print Network [OSTI]

    Pande, Paritosh

    2014-05-16T23:59:59.000Z

    imaging (FLIM) with optical coherence tomography (OCT), for the diagnosis of atherosclerosis and oral cancer. FLIM is a fluorescence imaging technique that is capable of providing information about auto fluorescent tissue biomolecules. OCT on the other...

  10. Postmortem analysis of sand grain crushing from pile interface using X-ray tomography

    SciTech Connect (OSTI)

    Silva, I. Matias; Combe, Gaeel; Foray, Pierre; Flin, Frederic; Lesaffre, Bernard [Universite de Grenoble, 3SR Lab, UMR 5521 Grenoble-INP, UJF-Grenoble 1, CNRS, Grenoble, France CEN, CNRM-GAME UMR 3589, Meteo France - CNRS, Grenoble (France)

    2013-06-18T23:59:59.000Z

    Pile foundations of offshore platforms, wind and water turbines are typically subjected to a variety of cyclic loading paths due to their complex environment. While many studies focus on global pile behaviour, the soil-pile interface is explored here by a micromechanical study of the soil layer in contact with the pile surface. This work is devoted to the analysis of frozen post-mortem silica sand samples recovered at the pile interface following installation and cyclic loading tests in a calibration chamber using x-ray tomography. An experimental procedure developed for three dimensional (3D) snow imaging was adapted for the recovery of the in-situ sand samples to preserve their structure during tomography scans. 3D images at a pixel size of 7 {mu}m were then obtained using a cryogenic cell. Results confirm the presence of a shear band at the pile surface as well as void ratios changes in the direction of the pile's radius.

  11. Quantum process tomography and Linblad estimation of a solid state qubit

    E-Print Network [OSTI]

    M. Howard; J. Twamley; C. Wittmann; T. Gaebel; F. Jelezko; J. Wrachtrup

    2006-01-25T23:59:59.000Z

    We present an example of quantum process tomography (QPT) performed on a single solid state qubit. The qubit used is two energy levels of the triplet state in the Nitrogen-Vacancy defect in Diamond. Quantum process tomography is applied to a qubit which has been allowed to decohere for three different time periods. In each case the process is found in terms of the chi matrix representation and the affine map representation. The discrepancy between experimentally estimated process and the closest physically valid process is noted. The results of QPT performed after three different decoherence times are used to find the error generators, or Lindblad operators, for the system, using the technique introduced by Boulant et al. [N. Boulant, T.F. Havel, M.A. Pravia and D.G. Cory, Phys. Rev. A 67, 042322 (2003)].

  12. X-Ray Digital Radiography and Computed Tomography Characterization of Targets

    SciTech Connect (OSTI)

    Sain, J D; Brown, W D; Chinn, D J; Martz Jr., H E; Morales, K E; Schneberk, D J; Updike, E O

    2008-04-16T23:59:59.000Z

    The summary of this report is: (1) The Xradia Micro XCT and LLNL CCAT x-ray systems are used to nondestructively characterize a variety of materials, assemblies, and reference standard components; (2) The digital radiograph (DR) and computed tomography (CT) image data may be used for metrology, quality control, and defect detection; and (3) The ability to detect and characterize imperfections leads to improvements in the manufacturing processes for assemblies.

  13. The Quasi-Reversibility Method for the Thermoacoustic Tomography and a Coefficient Inverse Problem

    E-Print Network [OSTI]

    Klibanov, Michael V; Nechaev, Dmitriy V; Kuzhuget, Andrey V

    2007-01-01T23:59:59.000Z

    An inverse problem of the determination of an initial condition in a hyperbolic equation from the lateral Cauchy data is considered. This problem has applications to the thermoacoustic tomography, as well as to linearized coefficient inverse problems of acoustics and electromagnetics. A new version of the quasi-reversibility method is described. This version requires a new Lipschitz stability estimate, which is obtained via the Carleman estimate. Numerical results are presented.

  14. The Quasi-Reversibility Method for the Thermoacoustic Tomography and a Coefficient Inverse Problem

    E-Print Network [OSTI]

    Michael V Klibanov; Sergey I Kabanikhin; Dmitriy V Nechaev; Andrey V Kuzhuget

    2007-12-02T23:59:59.000Z

    An inverse problem of the determination of an initial condition in a hyperbolic equation from the lateral Cauchy data is considered. This problem has applications to the thermoacoustic tomography, as well as to linearized coefficient inverse problems of acoustics and electromagnetics. A new version of the quasi-reversibility method is described. This version requires a new Lipschitz stability estimate, which is obtained via the Carleman estimate. Numerical results are presented.

  15. Application of computed tomography to enhanced oil recovery studies in naturally fractured reservoirs 

    E-Print Network [OSTI]

    Fineout, James Mark

    1992-01-01T23:59:59.000Z

    , they developed both a single matrix block model and a dual matrix block model with variable fracture width. These tests related imbibition theory with regard to matrix block size, permeability and fluid viscosity affects on oil recovery. They also determined... in naturally fractured reservoirs have relied upon material balance calculations to determine saturation changes. Through the use of Computed Tomography scanning, we have developed a technique not only to determine saturation changes but also positional...

  16. A simple setup for neutron tomography at the Portuguese Nuclear Research Reactor

    E-Print Network [OSTI]

    M. A. Stanojev Pereira; J. G. Marques; R. Pugliesi

    2012-05-15T23:59:59.000Z

    A simple setup for neutron radiography and tomography was recently installed at the Portuguese Research Reactor. The objective of this work was to determine the operational characteristics of the installed setup, namely the irradiation time to obtain the best dynamic range for individual images and the spatial resolution. The performance of the equipment was demonstrated by imaging a fragment of a 17th century decorative tile.

  17. On single qubit quantum process tomography for trace-preserving and nontrace-preserving maps

    E-Print Network [OSTI]

    Ramesh Bhandari; Nicholas A. Peters

    2015-02-03T23:59:59.000Z

    We review single-qubit quantum process tomography for trace-preserving and nontrace-preserving processes, and derive explicit forms of the general constraints for fitting experimental data. These forms provide additional insight into the structure of the process matrix as well as reveal a tighter bound on the trace of a nontrace-preserving process than has been previously stated. We also describe, for completeness, how to incorporate measured imperfect input states.

  18. 3D and 4D magnetic susceptibility tomography based on complex MR images

    DOE Patents [OSTI]

    Chen, Zikuan; Calhoun, Vince D

    2014-11-11T23:59:59.000Z

    Magnetic susceptibility is the physical property for T2*-weighted magnetic resonance imaging (T2*MRI). The invention relates to methods for reconstructing an internal distribution (3D map) of magnetic susceptibility values, .chi. (x,y,z), of an object, from 3D T2*MRI phase images, by using Computed Inverse Magnetic Resonance Imaging (CIMRI) tomography. The CIMRI technique solves the inverse problem of the 3D convolution by executing a 3D Total Variation (TV) regularized iterative convolution scheme, using a split Bregman iteration algorithm. The reconstruction of .chi. (x,y,z) can be designed for low-pass, band-pass, and high-pass features by using a convolution kernel that is modified from the standard dipole kernel. Multiple reconstructions can be implemented in parallel, and averaging the reconstructions can suppress noise. 4D dynamic magnetic susceptibility tomography can be implemented by reconstructing a 3D susceptibility volume from a 3D phase volume by performing 3D CIMRI magnetic susceptibility tomography at each snapshot time.

  19. Positron Emission Tomography/Computed Tomography Imaging of Residual Skull Base Chordoma Before Radiotherapy Using Fluoromisonidazole and Fluorodeoxyglucose: Potential Consequences for Dose Painting

    SciTech Connect (OSTI)

    Mammar, Hamid, E-mail: hamid.mammar@unice.fr [Radiation Oncology Department, Antoine Lacassagne Center, Nice (France) [Radiation Oncology Department, Antoine Lacassagne Center, Nice (France); CNRS-UMR 6543, Institute of Developmental Biology and Cancer, University of Nice Sophia Antipolis, Nice (France); Kerrou, Khaldoun; Nataf, Valerie [Department of Nuclear Medicine and Radiopharmacy, Tenon Hospital, and University Pierre et Marie Curie, Paris (France)] [Department of Nuclear Medicine and Radiopharmacy, Tenon Hospital, and University Pierre et Marie Curie, Paris (France); Pontvert, Dominique [Proton Therapy Center of Orsay, Curie Institute, Paris (France)] [Proton Therapy Center of Orsay, Curie Institute, Paris (France); Clemenceau, Stephane [Department of Neurosurgery, Pitie-Salpetriere Hospital, Paris (France)] [Department of Neurosurgery, Pitie-Salpetriere Hospital, Paris (France); Lot, Guillaume [Department of Neurosurgery, Adolph De Rothschild Foundation, Paris (France)] [Department of Neurosurgery, Adolph De Rothschild Foundation, Paris (France); George, Bernard [Department of Neurosurgery, Lariboisiere Hospital, Paris (France)] [Department of Neurosurgery, Lariboisiere Hospital, Paris (France); Polivka, Marc [Department of Pathology, Lariboisiere Hospital, Paris (France)] [Department of Pathology, Lariboisiere Hospital, Paris (France); Mokhtari, Karima [Department of Pathology, Pitie-Salpetriere Hospital, Paris (France)] [Department of Pathology, Pitie-Salpetriere Hospital, Paris (France); Ferrand, Regis; Feuvret, Loiec; Habrand, Jean-louis [Proton Therapy Center of Orsay, Curie Institute, Paris (France)] [Proton Therapy Center of Orsay, Curie Institute, Paris (France); Pouyssegur, Jacques; Mazure, Nathalie [CNRS-UMR 6543, Institute of Developmental Biology and Cancer, University of Nice Sophia Antipolis, Nice (France)] [CNRS-UMR 6543, Institute of Developmental Biology and Cancer, University of Nice Sophia Antipolis, Nice (France); Talbot, Jean-Noeel [Department of Nuclear Medicine and Radiopharmacy, Tenon Hospital, and University Pierre et Marie Curie, Paris (France)] [Department of Nuclear Medicine and Radiopharmacy, Tenon Hospital, and University Pierre et Marie Curie, Paris (France)

    2012-11-01T23:59:59.000Z

    Purpose: To detect the presence of hypoxic tissue, which is known to increase the radioresistant phenotype, by its uptake of fluoromisonidazole (18F) (FMISO) using hybrid positron emission tomography/computed tomography (PET/CT) imaging, and to compare it with the glucose-avid tumor tissue imaged with fluorodeoxyglucose (18F) (FDG), in residual postsurgical skull base chordoma scheduled for radiotherapy. Patients and Methods: Seven patients with incompletely resected skull base chordomas were planned for high-dose radiotherapy (dose {>=}70 Gy). All 7 patients underwent FDG and FMISO PET/CT. Images were analyzed qualitatively by visual examination and semiquantitatively by computing the ratio of the maximal standardized uptake value (SUVmax) of the tumor and cerebellum (T/C R), with delineation of lesions on conventional imaging. Results: Of the eight lesion sites imaged with FDG PET/CT, only one was visible, whereas seven of nine lesions were visible on FMISO PET/CT. The median SUVmax in the tumor area was 2.8 g/mL (minimum 2.1; maximum 3.5) for FDG and 0.83 g/mL (minimum 0.3; maximum 1.2) for FMISO. The T/C R values ranged between 0.30 and 0.63 for FDG (median, 0.41) and between 0.75 and 2.20 for FMISO (median,1.59). FMISO T/C R >1 in six lesions suggested the presence of hypoxic tissue. There was no correlation between FMISO and FDG uptake in individual chordomas (r = 0.18, p = 0.7). Conclusion: FMISO PET/CT enables imaging of the hypoxic component in residual chordomas. In the future, it could help to better define boosted volumes for irradiation and to overcome the radioresistance of these lesions. No relationship was founded between hypoxia and glucose metabolism in these tumors after initial surgery.

  20. Comparison of Physical Examination and Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography 4-6 Months After Radiotherapy to Assess Residual Head-and-Neck Cancer

    SciTech Connect (OSTI)

    Zundel, M. Tracy [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Michel, Michelle A. [Department of Radiology, Medical College of Wisconsin, Milwaukee, WI (United States); Schultz, Christopher J. [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Maheshwari, Mohit [Department of Radiology, Medical College of Wisconsin, Milwaukee, WI (United States); Wong, Stuart J. [Department of Neoplastic and Related Disorders, Medical College of Wisconsin, Milwaukee, WI (United States); Campbell, Bruce H.; Massey, Becky L.; Blumin, Joel [Department of Otolaryngology, Medical College of Wisconsin, Milwaukee, WI (United States); Wilson, J. Frank [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Wang, Dian, E-mail: dwang@mcw.edu [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States)

    2011-12-01T23:59:59.000Z

    Purpose: To retrospectively compare fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) and physical examination 4-6 months after radiotherapy for assessing residual head-and-neck cancer (HNC). Methods and Materials: From July 2002 through March 2006, 52 HNC patients underwent definitive radiotherapy or chemoradiotherapy. Categoric assessments of residual tumor by PET/CT and physical examination 4-6 months after therapy were correlated and compared with clinical outcomes. Pretreatment data, including tumor stage and primary site standardized uptake value, were also gathered retrospectively and correlated with clinical outcomes. Median follow-up time was 58 months. Results: Twenty-one patients had either locoregionally 'positive' (17 of 21) or 'equivocal' (4 of 21) PET/CT scans, whereas 31 patients had locoregionally negative scans. Four patients failed treatment and had biopsy-confirmed residual or recurrent local disease. All patients, including patients with locally suspicious scans or examinations who refused biopsies, were followed clinically for a minimum of 29 months after therapy, with no other cases of treatment failure detected during this time. No patient had residual nodal disease after therapy. Sensitivities of PET/CT vs. physical examination for early detection of treatment failure were 100% vs. 50%, whereas the specificities of the two modalities were 64.6% vs. 89.6%, respectively. Higher initial T stage and American Joint Commission on Cancer stage correlated with increased incidence of positive/equivocal PET/CT results and treatment failure. Maximal standardized uptake value was not predictive of any clinical outcome. Conclusions: A negative result on PET/CT obtained 4-6 months after radiotherapy is highly sensitive and correlates with successful locoregional control. Patients with negative scans may reasonably be spared invasive diagnostic procedures, such as biopsy and neck dissection, unless recurrent disease is suspected on clinical grounds. Close follow-up is prudent for HNC patients with abnormal findings on posttherapy PET/CT scan.

  1. Phase contrast tomography of the mouse cochlea at microfocus x-ray sources

    SciTech Connect (OSTI)

    Bartels, Matthias; Krenkel, Martin [Institute for X-Ray Physics, University of Göttingen, Göttingen (Germany)] [Institute for X-Ray Physics, University of Göttingen, Göttingen (Germany); Hernandez, Victor H. [InnerEarLab, Department of Otolaryngology, University Medical Center Göttingen, Göttingen (Germany) [InnerEarLab, Department of Otolaryngology, University Medical Center Göttingen, Göttingen (Germany); Bernstein Focus for Neurotechnology, University of Göttingen, Göttingen (Germany); Moser, Tobias [InnerEarLab, Department of Otolaryngology, University Medical Center Göttingen, Göttingen (Germany) [InnerEarLab, Department of Otolaryngology, University Medical Center Göttingen, Göttingen (Germany); Bernstein Focus for Neurotechnology, University of Göttingen, Göttingen (Germany); Center for Nanoscopy and Molecular Physiology of the Brain, Göttingen (Germany); Salditt, Tim [Institute for X-Ray Physics, University of Göttingen, Göttingen (Germany) [Institute for X-Ray Physics, University of Göttingen, Göttingen (Germany); Center for Nanoscopy and Molecular Physiology of the Brain, Göttingen (Germany)

    2013-08-19T23:59:59.000Z

    We present phase contrast x-ray tomography of functional soft tissue within the bony cochlear capsule of mice, carried out at laboratory microfocus sources with well-matched source, detector, geometry, and reconstruction algorithms at spatial resolutions down to 2 ?m. Contrast, data quality and resolution enable the visualization of thin membranes and nerve fibers as well as automated segmentation of surrounding bone. By complementing synchrotron radiation imaging techniques, a broad range of biomedical applications becomes possible as demonstrated for optogenetic cochlear implant research.

  2. High-resolution retinal imaging using adaptive optics and Fourier-domain optical coherence tomography

    DOE Patents [OSTI]

    Olivier, Scot S. (Livermore, CA); Werner, John S. (Davis, CA); Zawadzki, Robert J. (Sacramento, CA); Laut, Sophie P. (Pasedena, CA); Jones, Steven M. (Livermore, CA)

    2010-09-07T23:59:59.000Z

    This invention permits retinal images to be acquired at high speed and with unprecedented resolution in three dimensions (4.times.4.times.6 .mu.m). The instrument achieves high lateral resolution by using adaptive optics to correct optical aberrations of the human eye in real time. High axial resolution and high speed are made possible by the use of Fourier-domain optical coherence tomography. Using this system, we have demonstrated the ability to image microscopic blood vessels and the cone photoreceptor mosaic.

  3. Transhepatic Approach for Percutaneous Computed-Tomography-Guided Radiofrequency Ablation of Renal Cell Carcinoma

    SciTech Connect (OSTI)

    Iguchi, Toshihiro, E-mail: iguchi@cc.okayama-u.ac.jp; Hiraki, Takao; Gobara, Hideo; Mukai, Takashi; Hase, Soichiro; Fujiwara, Hiroyasu; Tajiri, Nobuhisa; Sakurai, Jun; Mimura, Hidefumi [Okayama University Medical School, Department of Radiology (Japan); Saika, Takashi; Kumon, Hiromi [Okayama University Medical School, Department of Urology (Japan); Kanazawa, Susumu [Okayama University Medical School, Department of Radiology (Japan)

    2007-07-15T23:59:59.000Z

    We performed percutaneously radiofrequency (RF) ablation of 5 renal cell carcinomas (mean diameter 26 {+-} 15 mm) with computed-tomography (CT) fluoroscopic guidance using the transhepatic route. The RF electrode was successfully advanced into all tumors. RF ablation caused one minor complication (small asymptomatic perirenal hematoma); no major complications occurred. The follow-up contrast-enhanced CT images showed no local tumor progression of any tumors in a median period of 10 months (range 3-14 months). In conclusion, it seems that this transhepatic approach is safe and can be an alternative method for electrode insertion during RF ablation of selected renal tumors.

  4. Computed tomography of the spleen and liver in sickle cell disease

    SciTech Connect (OSTI)

    Magid, D.; Fishman, E.K.; Siegelman, S.S.

    1984-08-01T23:59:59.000Z

    The spleen was assessed in 10 patients with sickle cell disease studied with computed tomography (CT) for abdominal pain and/or unexplained fever. Patients with homozygous sickle cell anemia were found to have small, densely calcified spleens with occasional low-density infarcts. Five of six had hepatomegaly, and there was one case each of hepatic abscess, infarcts, and hemochromatosis. All patients with heterozygous sickle cell disease were found to have splenomegaly, with a variety of findings including acute hemorrhage, acute and chronic infarcts, rupture, and possible sequestration. It was concluded that CT is useful for evaluating the status of the spleen and liver in symptomatic patients with sickle cell disease.

  5. New Cyclotron Targetry to Enhance F-18 clinical Position Emission Tomography

    SciTech Connect (OSTI)

    J. Michael Doster

    2008-12-19T23:59:59.000Z

    This project proposes to develop cyclotron targets that produce F-18 for clinical Positron Emission Tomography (PET) at significantly higher rates than that available from current targetry. This production rate of 18F is directly proportional to the beam current. Higher beam currents would result in increased 18F production but would be accompanied by higher heat loads to the target. The beam power available in most commercial cyclotrons exceeds the heat removal capacity of current target technology by a factor of two to four, significantly limiting the production rate of Fluorine-18.

  6. On the injectivity of the circular Radon transform arising in thermoacoustic tomography

    E-Print Network [OSTI]

    Gaik Ambartsoumian; Peter Kuchment

    2004-12-25T23:59:59.000Z

    The circular Radon transform integrates a function over the set of all spheres with a given set of centers. The problem of injectivity of this transform (as well as inversion formulas, range descriptions, etc.) arises in many fields from approximation theory to integral geometry, to inverse problems for PDEs, and recently to newly developing types of tomography. The article discusses known and provides new results that one can obtain by methods that essentially involve only the finite speed of propagation and domain dependence for the wave equation.

  7. A New Numerical Algorithm for Thermoacoustic and Photoacoustic Tomography with Variable Sound Speed

    E-Print Network [OSTI]

    Qian, Jianliang; Uhlmann, Gunther; Zhao, Hongkai

    2011-01-01T23:59:59.000Z

    We present a new algorithm for reconstructing an unknown source in Thermoacoustic and Photoacoustic Tomography based on the recent advances in understanding the theoretical nature of the problem. We work with variable sound speeds that might be also discontinuous across some surface. The latter problem arises in brain imaging. The new algorithm is based on an explicit formula in the form of a Neumann series. We present numerical examples with non-trapping, trapping and piecewise smooth speeds, as well as examples with data on a part of the boundary. These numerical examples demonstrate the robust performance of the new algorithm.

  8. The use of optical coherence tomography for morphological study of scaffolds

    SciTech Connect (OSTI)

    Veksler, B A; Kuz'min, V L; Kobzev, E D; Meglinski, I V

    2012-05-31T23:59:59.000Z

    Aimed at possible widening of the optical coherence tomography (OCT) field of application, an attempt is made to use OCT in tissue engineering and cell transplantology as a tool for morphological studies of substrate materials by the example of scaffolds. By means of the traditional fibreoptical OCT scheme the images of inner structure of scaffolds are obtained, and simultaneously the spatial distribution of the intralipid flow velocity is reconstructed using the Doppler OCT. It is shown that combined use of traditional OCT and Doppler OCT schemes allows revealing the regions of the scaffold demonstrating optimal effect of shear stress, which is a key factor of cell growth.

  9. Electrical impedance tomography spectroscopy method for characterising particles in solid-liquid phase

    SciTech Connect (OSTI)

    Zhao, Yanlin [Department of Thermal Energy Engineering, College of Mechanical and Transportation Engineering, China University of Petroleum, Beijing, 102249 (China); Wang, Mi [Institute of Particle Science and Engineering, School of Process, Environmental and Materials Engineering, University of Leeds, Leeds LS2 9JT (China); Yao, Jun [School of Energy Research, Xiamen University, Xiamen 361005 (China)

    2014-04-11T23:59:59.000Z

    Electrical impedance tomography (EIT) is one of the process tomography techniques to provide an on-line non-invasive imaging for multiphase flow measurement. With EIT measurements, the images of impedance real part, impedance imaginary part, phase angle, and magnitude can be obtained. However, most of the applications of EIT in the process industries rely on the conductivity difference between two phases in fluids to obtain the concentration profiles. It is not common to use the imaginary part or phase angle due to the dominant change in conductivity or complication in the use of other impedance information. In a solid-liquid two phases system involving nano- or submicro-particles, characterisation of particles (e.g. particle size and concentration) have to rely on the measurement of impedance phase angle or imaginary part. Particles in a solution usually have an electrical double layer associated with their surfaces and can form an induced electrical dipole moment due to the polarization of the electrical double layer under the influence of an alternating electric field. Similar to EIT, electrical impedance spectroscopy (EIS) measurement can record the electrical impedance data, including impedance real part, imaginary part and phase angle (?), which are caused by the polarization of the electrical double layer. These impedance data are related to the particle characteristics e.g. particle size, particle and ionic concentrations in the aqueous medium, therefore EIS method provides a capability for characterising the particles in suspensions. Electrical impedance tomography based on EIS measurement or namely, electrical impedance tomography spectroscopy (EITS) could image the spatial distribution of particle characteristics. In this paper, a new method, including test set-up and data analysis, for characterisation of particles in suspensions are developed through the experimental approach. The experimental results on tomographic imaging of colloidal particles based on EIS measurement using a sensor of 8 electrodes are reported. Results have demonstrated the potential as well as revealed the challenge in the use of EIS and EITS for characterisation of particle in suspension.

  10. International Conference on Fully 3D Reconstruction in Radiology and Nuclear Medicine, Linau, Germany, July 9-13, 2007 Abstract--Four-dimensional computed tomography (4D-CT)

    E-Print Network [OSTI]

    , Germany, July 9-13, 2007 Abstract--Four-dimensional computed tomography (4D-CT) plays an important role computed tomography (4D-CT) with respiratory gating provides dynamic volume imaging datasets of the moving

  11. THE SLOAN DIGITAL SKY SURVEY CO-ADD: CROSS-CORRELATION WEAK LENSING AND TOMOGRAPHY OF GALAXY CLUSTERS

    SciTech Connect (OSTI)

    Simet, Melanie; Dodelson, Scott [Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States); Kubo, Jeffrey M.; Annis, James T.; Hao Jiangang; Johnston, David; Lin, Huan; Soares-Santos, Marcelle [Center for Particle Astrophysics, Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); Reis, Ribamar R. R. [Instituto de Fisica, Universidade Federal do Rio de Janeiro (Brazil); Seo, Hee-Jong [Berkeley Center for Cosmological Physics and Berkeley Lab, University of California, Berkeley, CA 94720 (United States)

    2012-04-01T23:59:59.000Z

    The shapes of distant galaxies are sheared by intervening galaxy clusters. We examine this effect in Stripe 82, a 275 deg{sup 2} region observed multiple times in the Sloan Digital Sky Survey (SDSS) and co-added to achieve greater depth. We obtain a mass-richness calibration that is similar to other SDSS analyses, demonstrating that the co-addition process did not adversely affect the lensing signal. We also propose a new parameterization of the effect of tomography on the cluster lensing signal which does not require binning in redshift, and we show that using this parameterization we can detect tomography for stacked clusters at varying redshifts. Finally, due to the sensitivity of the tomographic detection to accurately marginalize over the effect of the cluster mass, we show that tomography at low redshift (where dependence on exact cosmological models is weak) can be used to constrain mass profiles in clusters.

  12. Breast tumor segmentation in high resolution x-ray phase contrast analyzer based computed tomography

    SciTech Connect (OSTI)

    Brun, E., E-mail: emmanuel.brun@esrf.fr [European Synchrotron Radiation Facility (ESRF), Grenoble 380000, France and Department of Physics, Ludwig-Maximilians University, Garching 85748 (Germany); Grandl, S.; Sztrókay-Gaul, A.; Gasilov, S. [Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, 81377 Munich (Germany); Barbone, G. [Department of Physics, Harvard University, Cambridge, Massachusetts 02138 (United States); Mittone, A.; Coan, P. [Department of Physics, Ludwig-Maximilians University, Garching 85748, Germany and Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, 81377 Munich (Germany); Bravin, A. [European Synchrotron Radiation Facility (ESRF), Grenoble 380000 (France)

    2014-11-01T23:59:59.000Z

    Purpose: Phase contrast computed tomography has emerged as an imaging method, which is able to outperform present day clinical mammography in breast tumor visualization while maintaining an equivalent average dose. To this day, no segmentation technique takes into account the specificity of the phase contrast signal. In this study, the authors propose a new mathematical framework for human-guided breast tumor segmentation. This method has been applied to high-resolution images of excised human organs, each of several gigabytes. Methods: The authors present a segmentation procedure based on the viscous watershed transform and demonstrate the efficacy of this method on analyzer based phase contrast images. The segmentation of tumors inside two full human breasts is then shown as an example of this procedure’s possible applications. Results: A correct and precise identification of the tumor boundaries was obtained and confirmed by manual contouring performed independently by four experienced radiologists. Conclusions: The authors demonstrate that applying the watershed viscous transform allows them to perform the segmentation of tumors in high-resolution x-ray analyzer based phase contrast breast computed tomography images. Combining the additional information provided by the segmentation procedure with the already high definition of morphological details and tissue boundaries offered by phase contrast imaging techniques, will represent a valuable multistep procedure to be used in future medical diagnostic applications.

  13. Quantum Process Tomography of an Optically-Controlled Kerr Non-linearity

    E-Print Network [OSTI]

    Connor Kupchak; Samuel Rind; Bertus Jordaan; Eden Figueroa

    2015-05-14T23:59:59.000Z

    Any optical quantum information processing machine would be comprised of fully-characterized constituent devices for both single state manipulations and tasks involving the interaction between multiple quantum optical states. Ideally for the latter, would be an apparatus capable of deterministic optical phase shifts that operate on input quantum states with the action mediated solely by auxiliary signal fields. Here we present the complete experimental characterization of a system designed for optically controlled phase shifts acting on single-photon level probe coherent states. Our setup is based on a warm vapor of rubidium atoms under the conditions of electromagnetically induced transparency with its dispersion properties modified through the use of an optically triggered N-type Kerr non-linearity. We fully characterize the performance of our device by sending in a set of input probe states and measuring the corresponding output via balanced homodyne tomography and subsequently performing the technique of coherent state quantum process tomography. This method provides us with the precise knowledge of how our optical phase shift will modify any arbitrary input quantum state engineered in the mode of the reconstruction.

  14. 3D structural fluctuation of IgG1 antibody revealed by individual particle electron tomography

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhang, Xing [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Xi'an Jiaotong Univ., Xi'an, Shaanxi (China); Zhang, Lei [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Tong, Huimin [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Peng, Bo [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Rames, Matthew J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Zhang, Shengli [Xi'an Jiaotong Univ., Xi'an, Shaanxi (China); Ren, Gang [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-05-05T23:59:59.000Z

    Commonly used methods for determining protein structure, including X-ray crystallography and single-particle reconstruction, often provide a single and unique three-dimensional (3D) structure. However, in these methods, the protein dynamics and flexibility/fluctuation remain mostly unknown. Here, we utilized advances in electron tomography (ET) to study the antibody flexibility and fluctuation through structural determination of individual antibody particles rather than averaging multiple antibody particles together. Through individual-particle electron tomography (IPET) 3D reconstruction from negatively-stained ET images, we obtained 120 ab-initio 3D density maps at an intermediate resolution (~1–3 nm) from 120 individual IgG1 antibody particles. Using these maps as a constraint, we derived 120 conformations of the antibody via structural flexible docking of the crystal structure to these maps by targeted molecular dynamics simulations. Statistical analysis of the various conformations disclosed the antibody 3D conformational flexibility through the distribution of its domain distances and orientations. This blueprint approach, if extended to other flexible proteins, may serve as a useful methodology towards understanding protein dynamics and functions.

  15. Computed tomography of coals. Quarterly technical progress report No. 1, August 16, 1982-November 28, 1982

    SciTech Connect (OSTI)

    Maylotte, D. H.; Kosky, P. G.; Spiro, C. L.; Lamby, E. J.

    1982-01-01T23:59:59.000Z

    The purpose of this contract is to examine the utility and advantages of x-ray computed tomography (CT) for investigating the structure within coal and the changes that occur in these structures during such processes as combustion and gasification. The CT technique is noninvasive and nondestructive. It can produce interior views of the coal and, with a data acquisition time of ca 9 seconds, can be used for following many coal processes in real time. This is the first in-depth study of the application of the x-ray tomography technique to the problems in coal utilization, and consequently, considerable time will be spent in the early stages of this contract in examining CT pictures of coal and relating them to more conventional petrographic and mineral analyses. This phase of the work is being undertaken in Task 1 of the contract and is reported for this period. Building on this foundation, the succeeding tasks will follow changes in the coal structure during reaction. The first series of CT experiments is scheduled to take place on December 11-13, 1982, at the General Electric Company, Medical Systems Operation, Milwaukee, Wisconsin. 4 figures, 1 table.

  16. Study on creating hydraulic tomography for crystalline rock using frequency dependent elastic wave velocity

    SciTech Connect (OSTI)

    Yoshimura, K.; Sakashita, S. [Radioactive Waste Management Funding and Research Center, Tokyo (Japan); Ando, K.; Bruines, P. [Civil Engineering Technical Division, Obayashi Corporation, Tokyo (Japan); Blechschmidt, I. [National Cooperative for the Disposal of Radioactive Waste, Wettingen (Switzerland); Kickmaier, W. [University of Applied Sciences, Northern Switzerland, Brugg (Switzerland); Onishi, Y.; Nishiyama, S. [Graduate School of Engineering, Kyoto University, Kyoto (Japan)

    2007-07-01T23:59:59.000Z

    The objective of this study is to establish a technique to obtain hydraulic conductivity distribution in granite rock masses using seismic tomography. We apply the characteristic that elastic wave velocity disperses in fully saturated porous media on frequency and this velocity dispersion is governed by the hydraulic conductivity - this characteristic has been confirmed in laboratory experiments. The feasibility and design of the field experiment was demonstrated in a first step with numerical simulations. In a second step we applied the technique to the fractured granite at the Grimsel Test Site in Switzerland. The emphasis of the field campaign was on the evaluation of the range of applicability of this technique. The field campaign was structured in three steps, each one corresponding to a larger spatial scale. First, the seismic tomography was applied to a small area - the two boreholes were located at a distance of 1.5 m. In the following step, we selected a larger area, in which the distance of the boreholes amounts to 10 m and the field corresponds to a more complex geology. Finally we applied the testing to a field where the borehole distance was of the order of 75 m. We also drilled a borehole to confirm hydraulic characteristic and reviewed hydraulic model in the 1.5 m cross-hole location area. The results from the field campaign are presented and their application to the various fields are discussed and evaluated. (authors)

  17. Attenuation Correction of L-shell X-ray Fluorescence Computed Tomography Imaging

    E-Print Network [OSTI]

    Long, Liu; Bo, Ma; Qing, Xu; Lingtong, Yan; Li, Li; Songlin, Feng; Xiangqian, Feng

    2014-01-01T23:59:59.000Z

    X-ray Fluorescence Computed Tomography(XFCT) is a prevalent experimental technique which is utilized to investigate the spatial distribution of elements in sample. The sensitivity of L-shell XFCT of some elements is lower than that of K-shell XFCT. However, the image reconstruction for this technique has much more problems than that of transmission tomography, one of which is self-absorption. In the present work, a novel strategy was developed to deal with such problems. But few researches are concerned on attenuation correction of L-shell XFCT that are essential to get accurate reconstructed image. We make use of the known quantities and the unknown elemental concentration of interest to express the unknown attenuation maps. And then the attenuation maps are added in the contribution value of the pixel in MLEM reconstruction method. Results indicate that the relative error is less than 14.1%, which is proved this method can correct L-shell XFCT very well.

  18. Double-Difference Tomography for Sequestration MVA [monitoring, verification, and accounting

    SciTech Connect (OSTI)

    Westman, Erik

    2012-12-31T23:59:59.000Z

    Analysis of synthetic data was performed to determine the most cost-effective tomographic monitoring system for a geologic carbon sequestration injection site. Double-difference tomographic inversion was performed on 125 synthetic data sets: five stages of CO2 plume growth, five seismic event regions, and five geophone arrays. Each resulting velocity model was compared quantitatively to its respective synthetic velocity model to determine an accuracy value. The results were examined to determine a relationship between cost and accuracy in monitoring, verification, and accounting applications using double-difference tomography. The geophone arrays with widely-varying geophone locations, both laterally and vertically, performed best. Additionally, double difference seismic tomography was performed using travel time data from a carbon sequestration site at the Aneth oil field in southeast Utah as part of a Department of Energy initiative on monitoring, verification, and accounting (MVA) of sequestered CO2. A total of 1,211 seismic events were recorded from a borehole array consisting of 22 geophones. Artificial velocity models were created to determine the ease with which different CO2 plume locations and sizes can be detected. Most likely because of the poor geophone arrangement, a low velocity zone in the Desert Creek reservoir can only be detected when regions of test site containing the highest ray path coverage are considered. MVA accuracy and precision may be improved through the use of a receiver array that provides more comprehensive ray path coverage.

  19. 3D structural fluctuation of IgG1 antibody revealed by individual particle electron tomography

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhang, Xing; Zhang, Lei; Tong, Huimin; Peng, Bo; Rames, Matthew J.; Zhang, Shengli; Ren, Gang

    2015-05-05T23:59:59.000Z

    Commonly used methods for determining protein structure, including X-ray crystallography and single-particle reconstruction, often provide a single and unique three-dimensional (3D) structure. However, in these methods, the protein dynamics and flexibility/fluctuation remain mostly unknown. Here, we utilized advances in electron tomography (ET) to study the antibody flexibility and fluctuation through structural determination of individual antibody particles rather than averaging multiple antibody particles together. Through individual-particle electron tomography (IPET) 3D reconstruction from negatively-stained ET images, we obtained 120 ab-initio 3D density maps at an intermediate resolution (~1–3 nm) from 120 individual IgG1 antibody particles. Using these maps as a constraint, wemore »derived 120 conformations of the antibody via structural flexible docking of the crystal structure to these maps by targeted molecular dynamics simulations. Statistical analysis of the various conformations disclosed the antibody 3D conformational flexibility through the distribution of its domain distances and orientations. This blueprint approach, if extended to other flexible proteins, may serve as a useful methodology towards understanding protein dynamics and functions.« less

  20. Toward Rapid Unattended X-ray Tomography of Large Planar Samples at 50-nm Resolution

    SciTech Connect (OSTI)

    Rudati, J.; Tkachuk, A.; Gelb, J.; Hsu, G.; Feng, Y.; Pastrick, R.; Lyon, A.; Trapp, D.; Beetz, T.; Chen, S.; Hornberger, B.; Seshadri, S.; Kamath, S.; Zeng, X.; Feser, M.; Yun, W. [Xradia, Inc., Concord, California (United States); Pianetta, P.; Andrews, J.; Brennan, S. [Stanford Synchrotron Radiation Lightsource, Stanford Linear Accelerator Center, Menlo Park, California (United States); Chu, Y. S. [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois (United States)] (and others)

    2009-04-19T23:59:59.000Z

    X-ray tomography at sub-50 nm resolution of small areas ({approx}15 {mu}mx15 {mu}m) are routinely performed with both laboratory and synchrotron sources. Optics and detectors for laboratory systems have been optimized to approach the theoretical efficiency limit. Limited by the availability of relatively low-brightness laboratory X-ray sources, exposure times for 3-D data sets at 50 nm resolution are still many hours up to a full day. However, for bright synchrotron sources, the use of these optimized imaging systems results in extremely short exposure times, approaching live-camera speeds at the Advanced Photon Source at Argonne National Laboratory near Chicago in the US These speeds make it possible to acquire a full tomographic dataset at 50 nm resolution in less than a minute of true X-ray exposure time. However, limits in the control and positioning system lead to large overhead that results in typical exposure times of {approx}15 min currently.We present our work on the reduction and elimination of system overhead and toward complete automation of the data acquisition process. The enhancements underway are primarily to boost the scanning rate, sample positioning speed, and illumination homogeneity to performance levels necessary for unattended tomography of large areas (many mm{sup 2} in size). We present first results on this ongoing project.

  1. Time-frequency quantum process tomography of parametric down-conversion

    E-Print Network [OSTI]

    Malte Avenhaus; Benjamin Brecht; Kaisa Laiho; Christine Silberhorn

    2014-06-17T23:59:59.000Z

    Parametric down-conversion (PDC) is the established standard for the practical generation of a multiplicity of quantum optical states. These include two-mode squeezed vacuum, heralded non-Gaussian states and entangled photon pairs. Detailed theoretical studies provide insight into the time-frequency (TF) structure of PDC, which are governed by the complex-valued joint spectral amplitude (JSA) function. However in experiments, the TF structure of PDC is mostly characterised by intensity measurementsthat forbid access to the important phase of the JSA. In this paper, we present an amplitude-sensitive quantum process tomography technique that combines methods from ultrafast optics and classical three-wave mixing. Our approach facilitates a direct and phase-sensitive time-frequency tomography of PDC with high spectral resolution and excellent signal-to-noise ratio. This is important for all quantum optical applications, which rely on engineered parametric processes and base on minute knowledge of the quantum wave-function for the generation of tailored photonic quantum states.

  2. Ten-Year Outcomes: The Clinical Utility of Single Photon Emission Computed Tomography/Computed Tomography Capromab Pendetide (Prostascint) in a Cohort Diagnosed With Localized Prostate Cancer

    SciTech Connect (OSTI)

    Ellis, Rodney J., E-mail: rodney.ellis@case.edu [Department of Radiation Oncology, University Hospitals, Case Medical Center and Case Western Reserve University School of Medicine, Cleveland, OH (United States); Department of Radiology, Northeastern Ohio Universities College of Medicine, Rootstown, OH (United States); Kaminsky, Deborah A. [Division of Radiation Therapy, Aultman Hospital, Canton, OH (United States); Zhou, Esther H. [Center for Drug Evaluation and Research, U.S.A. Food and Drug Administration, Silver spring, MD (United States); Fu, Pingfu [Department of Epidemiology and Biostatistics, Case Western Reserve University School of Medicine, Cleveland, OH (United States); Chen, Wei-Dong [Genetic Branch/Center for Cancer Research, National Cancer Institute/National Institutes of Health, and the National Naval Medical Center, Bethesda, MD (United States); Brelin, Alaina [Northeastern Ohio Universities College of Medicine, Rootstown, OH (United States); Faulhaber, Peter F. [Department of Radiology, University Hospitals, Case Medical Center and Case Western Reserve University School of Medicine, Cleveland, OH (United States); Bodner, Donald [Department of Urology, University Hospitals, Case Medical Center and Case Western Reserve University School of Medicine, Cleveland, OH (United States)

    2011-09-01T23:59:59.000Z

    Purpose: To evaluate the clinical utility of capromab pendetide imaging with single photon emission computed tomography coregistration with computed tomography (SPECT/CT) in primary prostate cancer (CaP) for pretreatment prognostic staging and localization of biologic target volumes (BTV) for individualized image-guided radiotherapy dose escalation (IGRT-DE). Methods and Materials: Patients consecutively presenting for primary radiotherapy (February 1997 to December 2002), having a clinical diagnosis of localized CaP, were evaluated for tumor stage using conventional staging and SPECT/CT (N = 239). Distant metastatic uptake (mets) were identified by SPECT/CT in 22 (9.2%). None of the suspected mets could be clinically confirmed. Thus, all subjects were followed without alteration in disease management. The SPECT/CT pelvic images defined BTV for IGRT-DE (+150% brachytherapy dose) without (n = 150) or with (n = 89) external radiation of 45 Gy. The National Comprehensive Cancer Network criteria defined risk groups (RG). The median survivor follow-up was 7 years. Biochemical disease-free survival (bDFS) was reported by clinical nadir +2 ng/mL (CN+2) criteria. Statistical analyses included Kaplan-Meier, multivariate analysis, and Concordance-index models. Results: At 10-year analyses, overall survival was 84.8% and bDFS was 84.6%. With stratification by RG, CN+2 bDFS was 93.5% for the low-RG (n = 116), 78.7% for the intermediate-RG (n = 94), and 68.8% for the high-RG (n = 29), p = 0.0002. With stratification by pretreatment SPECT/CT findings, bDFS was 65.5% in patients with suspected mets (n = 22) vs. 86.6% in patients with only localized uptake (n = 217), p = 0.0014. CaP disease-specific survival (DSS) was 97.7% for the cohort. With stratification by SPECT/CT findings, DSS was 86.4% (with suspected mets) vs. 99.0% (localized only), p = 0.0001. Using multivariate analysis, the DSS hazard ratio for SPECT/CT findings (mets vs. localized) was 3.58 (p = 0.0026). Concordance-index tests, based on all data, by CN+2 bDFS criteria were 0.710 for RG alone and 0.773 for SPECT/CT + RG. Conclusions: Through long-term outcomes we demonstrate statistically significant bDFS and DSS predictive value for pretreatment capromab pendetide SPECT/CT imaging in primary CaP. Dual clinical utility is demonstrated, using SPECT/CT to define BTV for individualized IGRT-DE.

  3. IEEE TRANSACTIONS ON NUCLEAR SCIENCE, VOL. 55, NO. 1, FEBRUARY 2008 501 Neutron Stimulated Emission Computed Tomography

    E-Print Network [OSTI]

    in the human body. NSECT uses a beam of fast neutrons that scatter inelastically from atomic nuclei in tissueIEEE TRANSACTIONS ON NUCLEAR SCIENCE, VOL. 55, NO. 1, FEBRUARY 2008 501 Neutron Stimulated Emission. Pedroni, and Carey E. Floyd, Jr. Abstract--Neutron stimulated emission computed tomography (NSECT

  4. Radiation dose reduction in medical CT through equally sloped tomography Benjamin P. Fahimian1,2,6

    E-Print Network [OSTI]

    Soatto, Stefano

    Council on Radiation Protection & Measurements10 , CT accounts for about 15% of the total radiological50Radiation dose reduction in medical CT through equally sloped tomography Benjamin P. Fahimian1 Department of Radiation Oncology, Stanford University, Stanford, CA 94305 3 Biomedical Physics

  5. Fluorescence optical diffusion tomography Adam B. Milstein, Seungseok Oh, Kevin J. Webb, Charles A. Bouman, Quan Zhang,

    E-Print Network [OSTI]

    tomography ODT is emerging as a powerful tissue imaging modality.1,2 In ODT, im- ages are comprised sources and detectors are used to recover the unknown parame- ters from a scattering model described to diffusion model computations. As a result of the nonlinear dependence of the diffusion equation photon flux

  6. Electrical impedance tomography of carbon nanotube composite Tsung-Chin Hou, Kenneth J. Loh, Jerome P. Lynch1

    E-Print Network [OSTI]

    Lynch, Jerome P.

    Electrical impedance tomography of carbon nanotube composite materials Tsung-Chin Hou, Kenneth J composites with the carbon nanotube significantly contributing to bulk material properties. One approach. Carbon nanotubes are included in the composite material by dispersing them in the polyanionic solution

  7. Derivation of site-specific relationships between hydraulic parameters and p-wave velocities based on hydraulic and seismic tomography

    SciTech Connect (OSTI)

    Brauchler, R.; Doetsch, J.; Dietrich, P.; Sauter, M.

    2012-01-10T23:59:59.000Z

    In this study, hydraulic and seismic tomographic measurements were used to derive a site-specific relationship between the geophysical parameter p-wave velocity and the hydraulic parameters, diffusivity and specific storage. Our field study includes diffusivity tomograms derived from hydraulic travel time tomography, specific storage tomograms, derived from hydraulic attenuation tomography, and p-wave velocity tomograms, derived from seismic tomography. The tomographic inversion was performed in all three cases with the SIRT (Simultaneous Iterative Reconstruction Technique) algorithm, using a ray tracing technique with curved trajectories. The experimental set-up was designed such that the p-wave velocity tomogram overlaps the hydraulic tomograms by half. The experiments were performed at a wellcharacterized sand and gravel aquifer, located in the Leine River valley near Göttingen, Germany. Access to the shallow subsurface was provided by direct-push technology. The high spatial resolution of hydraulic and seismic tomography was exploited to derive representative site-specific relationships between the hydraulic and geophysical parameters, based on the area where geophysical and hydraulic tests were performed. The transformation of the p-wave velocities into hydraulic properties was undertaken using a k-means cluster analysis. Results demonstrate that the combination of hydraulic and geophysical tomographic data is a promising approach to improve hydrogeophysical site characterization.

  8. Abstract-Proton Computed Tomography (CT) has important implications for both image-guided diagnosis and radiation

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Abstract- Proton Computed Tomography (CT) has important implications for both image-guided diagnosis and radiation therapy. For diagnosis, the fact that the patient dose committed by proton CT and contrast, may be exploited in dose-critical clinical settings. Proton CT is also the most appropriate

  9. Imaging of high-intensity focused ultrasound-induced lesions in soft biological tissue using thermoacoustic tomography

    E-Print Network [OSTI]

    Wang, Lihong

    thermoacoustic tomography Xing Jin, Yuan Xu, and Lihong V. Wanga) Optical Imaging Laboratory, Department December 2004) An imaging technology, thermoacoustic tomograpy (TAT), was applied to the visualization thermoacoustic sources in this tissue sample. The thermoacoustic signals were detected by an unfocused ultrasonic

  10. 2002 IEEE NSS/MIC pCT: Hartmut F.-W. Sadrozinski , SCIPP Towards Proton Computed Tomography

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    2002 IEEE NSS/MIC pCT: Hartmut F.-W. Sadrozinski , SCIPP SCIPPSCIPP Towards Proton Computed Tomography L. R. Johnson, B. Keeney, G. Ross, H. F.-W. Sadrozinski, A. Seiden, D.C. Williams, L. Zhang Santa Radiography MC Study #12;2002 IEEE NSS/MIC pCT: Hartmut F.-W. Sadrozinski , SCIPP SCIPPSCIPP Computed

  11. Experimental comparison of grating- and propagation-based hard X-ray phase tomography of soft tissue

    SciTech Connect (OSTI)

    Lang, S.; Schulz, G.; Müller, B. [Biomaterials Science Center, University of Basel, Basel (Switzerland); Zanette, I., E-mail: irene.zanette@tum.de [Physik-Department und Institut für Medizintechnik, Technische Universität München, Garching (Germany); European Synchrotron Radiation Facility, Grenoble (France); Dominietto, M. [Biomaterials Science Center, University of Basel, Basel (Switzerland); Institute for Biomedical Engineering, ETH Zürich, Zürich (Switzerland); Langer, M. [European Synchrotron Radiation Facility, Grenoble (France); Université de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA-LYON, Université de Lyon 1, Villeurbane (France); Rack, A.; Le Duc, G. [European Synchrotron Radiation Facility, Grenoble (France); David, C. [Laboratory for Micro- and Nanotechnology, Paul Scherrer Institut, Villigen (Switzerland); Mohr, J. [Institute of Microstructure Technology, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen (Germany); Pfeiffer, F. [Physik-Department und Institut für Medizintechnik, Technische Universität München, Garching (Germany); Weitkamp, T. [European Synchrotron Radiation Facility, Grenoble (France); Synchrotron Soleil, Gif-sur-Yvette (France)

    2014-10-21T23:59:59.000Z

    When imaging soft tissues with hard X-rays, phase contrast is often preferred over conventional attenuation contrast due its superior sensitivity. However, it is unclear which of the numerous phase tomography methods yields the optimized results at given experimental conditions. Therefore, we quantitatively compared the three phase tomography methods implemented at the beamline ID19 of the European Synchrotron Radiation Facility: X-ray grating interferometry (XGI), and propagation-based phase tomography, i.e., single-distance phase retrieval (SDPR) and holotomography (HT), using cancerous tissue from a mouse model and an entire heart of a rat. We show that for both specimens, the spatial resolution derived from the characteristic morphological features is about a factor of two better for HT and SDPR compared to XGI, whereas the XGI data generally exhibit much better contrast-to-noise ratios for the anatomical features. Moreover, XGI excels in fidelity of the density measurements, and is also more robust against low-frequency artifacts than HT, but it might suffer from phase-wrapping artifacts. Thus, we can regard the three phase tomography methods discussed as complementary. The application will decide which spatial and density resolutions are desired, for the imaging task and dose requirements, and, in addition, the applicant must choose between the complexity of the experimental setup and the one of data processing.

  12. BRUCE HOWE Chair and Professor , PhD 1986, UC San Diego. Ocean observatories, ocean acoustic tomography, sensor webs

    E-Print Network [OSTI]

    Frandsen, Jannette B.

    . NIHOUS Associate Professor, PhD 1983, UC Berkeley. Ocean Thermal Energy Conversion (OTEC), marineFaculty BRUCE HOWE Chair and Professor , PhD 1986, UC San Diego. Ocean observatories, ocean in the ocean, atmospheric and ionospheric tomography. KWOK FAI CHEUNG Professor , PhD 1991, British Columbia

  13. A constrained variable projection reconstruction method for photoacoustic computed tomography without accurate knowledge of transducer responses

    E-Print Network [OSTI]

    Sheng, Qiwei; Matthews, Thomas P; Xia, Jun; Zhu, Liren; Wang, Lihong V; Anastasio, Mark A

    2015-01-01T23:59:59.000Z

    Photoacoustic computed tomography (PACT) is an emerging computed imaging modality that exploits optical contrast and ultrasonic detection principles to form images of the absorbed optical energy density within tissue. When the imaging system employs conventional piezoelectric ultrasonic transducers, the ideal photoacoustic (PA) signals are degraded by the transducers' acousto-electric impulse responses (EIRs) during the measurement process. If unaccounted for, this can degrade the accuracy of the reconstructed image. In principle, the effect of the EIRs on the measured PA signals can be ameliorated via deconvolution; images can be reconstructed subsequently by application of a reconstruction method that assumes an idealized EIR. Alternatively, the effect of the EIR can be incorporated into an imaging model and implicitly compensated for during reconstruction. In either case, the efficacy of the correction can be limited by errors in the assumed EIRs. In this work, a joint optimization approach to PACT image r...

  14. Waveform Inversion with Source Encoding for Breast Sound Speed Reconstruction in Ultrasound Computed Tomography

    E-Print Network [OSTI]

    Wang, Kun; Anis, Fatima; Li, Cuiping; Duric, Neb; Anastasio, Mark A

    2015-01-01T23:59:59.000Z

    Ultrasound computed tomography (USCT) holds great promise for improving the detection and management of breast cancer. Because they are based on the acoustic wave equation, waveform inversion-based reconstruction methods can produce images that possess improved spatial resolution properties over those produced by ray-based methods. However, waveform inversion methods are computationally demanding and have not been applied widely in USCT breast imaging. In this work, source encoding concepts are employed to develop an accelerated USCT reconstruction method that circumvents the large computational burden of conventional waveform inversion methods. This method, referred to as the waveform inversion with source encoding (WISE) method, encodes the measurement data using a random encoding vector and determines an estimate of the sound speed distribution by solving a stochastic optimization problem by use of a stochastic gradient descent algorithm. Both computer-simulation and experimental phantom studies are conduc...

  15. Quantum Process Tomography of an Optically-Controlled Kerr Non-linearity

    E-Print Network [OSTI]

    Kupchak, Connor; Jordaan, Bertus; Figueroa, Eden

    2015-01-01T23:59:59.000Z

    Any optical quantum information processing machine would be comprised of fully-characterized constituent devices for both single state manipulations and tasks involving the interaction between multiple quantum optical states. Ideally for the latter, would be an apparatus capable of deterministic optical phase shifts that operate on input quantum states with the action mediated solely by auxiliary signal fields. Here we present the complete experimental characterization of a system designed for optically controlled phase shifts acting on single-photon level probe coherent states. Our setup is based on a warm vapor of rubidium atoms under the conditions of electromagnetically induced transparency with its dispersion properties modified through the use of an optically triggered N-type Kerr non-linearity. We fully characterize the performance of our device by sending in a set of input probe states and measuring the corresponding output via balanced homodyne tomography and subsequently performing the technique of ...

  16. Expectation propagation for nonlinear inverse problems – with an application to electrical impedance tomography

    SciTech Connect (OSTI)

    Gehre, Matthias, E-mail: mgehre@math.uni-bremen.de [Center for Industrial Mathematics, University of Bremen, Bremen D-28344 (Germany)] [Center for Industrial Mathematics, University of Bremen, Bremen D-28344 (Germany); Jin, Bangti, E-mail: bangti.jin@gmail.com [Department of Mathematics, University of California, Riverside, University Ave. 900, Riverside, CA 92521 (United States)] [Department of Mathematics, University of California, Riverside, University Ave. 900, Riverside, CA 92521 (United States)

    2014-02-15T23:59:59.000Z

    In this paper, we study a fast approximate inference method based on expectation propagation for exploring the posterior probability distribution arising from the Bayesian formulation of nonlinear inverse problems. It is capable of efficiently delivering reliable estimates of the posterior mean and covariance, thereby providing an inverse solution together with quantified uncertainties. Some theoretical properties of the iterative algorithm are discussed, and the efficient implementation for an important class of problems of projection type is described. The method is illustrated with one typical nonlinear inverse problem, electrical impedance tomography with complete electrode model, under sparsity constraints. Numerical results for real experimental data are presented, and compared with that by Markov chain Monte Carlo. The results indicate that the method is accurate and computationally very efficient.

  17. Atomic Scale Characterization of Compound Semiconductors using Atom Probe Tomography: Preprint

    SciTech Connect (OSTI)

    Gorman, B. P.; Guthrey, H.; Norman, A. G.; Al-Jassim, M.; Lawrence, D.; Prosa, T.

    2011-07-01T23:59:59.000Z

    Internal interfaces are critical in determining the performance of III-V multijunction solar cells. Studying these interfaces with atomic resolution using a combination of transmission electron microscopy (TEM), atom probe tomography (APT), and density functional calculations enables a more fundamental understanding of carrier dynamics in photovoltaic (PV) device structures. To achieve full atomic scale spatial and chemical resolution, data acquisition parameters in laser pulsed APT must be carefully studied to eliminate surface diffusion. Atom probe data with minimized group V ion clustering and expected stoichiometry can be achieved by adjusting laser pulse power, pulse repetition rate, and specimen preparation parameters such that heat flow away from the evaporating surface is maximized. Applying these improved analysis conditions to III-V based PV gives an atomic scale understanding of compositional and dopant profiles across interfaces and tunnel junctions and the initial stages of alloy clustering and dopant accumulation. Details on APT experimental methods and future in-situ instrumentation developments are illustrated.

  18. Nonstationary phase boundary estimation in electrical impedance tomography using unscented Kalman filter

    SciTech Connect (OSTI)

    Ijaz, Umer Zeeshan; Khambampati, Anil Kumar [Department of Electronic Engineering, Cheju National University, Cheju 690-756 (Korea, Republic of); Lee, Jeong Seong; Kim, Sin [Department of Nuclear and Energy Engineering, Cheju National University, Cheju 690-756 (Korea, Republic of); Kim, Kyung Youn [Department of Electronic Engineering, Cheju National University, Cheju 690-756 (Korea, Republic of)], E-mail: kyungyk@cheju.ac.kr

    2008-07-20T23:59:59.000Z

    In this paper, an effective nonstationary phase boundary estimation scheme in electrical impedance tomography is presented based on the unscented Kalman filter. The inverse problem is treated as a stochastic nonlinear state estimation problem with the nonstationary phase boundary (state) being estimated online with the aid of unscented Kalman filter. This research targets the industrial applications, such as imaging of stirrer vessel for detection of air distribution or detecting large air bubbles in pipelines. Within the domains, there exist 'voids' having zero conductivity. The design variables for phase boundary estimation are truncated Fourier coefficients. Computer simulations and experimental results are provided to evaluate the performance of unscented Kalman filter in comparison with extended Kalman filter to show a better performance of the unscented Kalman filter approach.

  19. X-ray tomography system to investigate granular materials during mechanical loading

    E-Print Network [OSTI]

    Athanassiadis, Athanasios G; Sidky, Emil; Pelizzari, Charles; Pan, Xiaochuan; Jaeger, Heinrich M

    2014-01-01T23:59:59.000Z

    We integrate a small and portable medical x-ray device with mechanical testing equipment to enable in-situ, non-invasive measurements of a granular material's response to mechanical loading. We employ an orthopedic C-arm as the x-ray source and detector to image samples mounted in the materials tester. We discuss the design of a custom rotation stage, which allows for sample rotation and tomographic reconstruction under applied compressive stress. We then discuss the calibration of the system for 3d computed tomography, as well as the subsequent image reconstruction process. Using this system to reconstruct packings of 3d-printed particles, we resolve packing features with 0.52 mm resolution in a (60 mm)$^3$ field of view. By analyzing the performance bounds of the system, we demonstrate that the reconstructions exhibit only moderate noise.

  20. Quantum State and Process Tomography of Energy Transfer Systems via Ultrafast Spectroscopy

    E-Print Network [OSTI]

    Joel Yuen-Zhou; Jacob J. Krich; Masoud Mohseni; Alán Aspuru-Guzik

    2011-10-28T23:59:59.000Z

    The description of excited state dynamics in multichromophoric systems constitutes both a theoretical and experimental challenge in modern physical chemistry. An experimental protocol which can systematically characterize both coherent and dissipative processes at the level of the evolving quantum state of the chromophores is desired. In this article, we show that a carefully chosen set of polarization controlled two-color heterodyned photon-echo experiments can be used to reconstruct the time-evolving density matrix of the one-exciton manifold of a heterodimer. This possibility in turn allows for a complete description of the excited state dynamics via quantum process tomography (QPT). Calculations on the dimer show that QPT can reveal rich information about system-bath interactions, which otherwise appear nontrivially hidden in the polarization monitored in standard four-wave mixing experiments. Our study presents a novel method for analyzing condensed phase experiments with a quantum information processing perspective.

  1. Compact MEMS-based Adaptive Optics Optical Coherence Tomography for Clinical Use

    SciTech Connect (OSTI)

    Chen, D; Olivier, S; Jones, S; Zawadzki, R; Evans, J; Choi, S; Werner, J

    2008-02-04T23:59:59.000Z

    We describe a compact MEMS-based adaptive optics (AO) optical coherence tomography system with improved AO performance and ease of clinical use. A typical AO system consists of a Shack-Hartmann wavefront sensor and a deformable mirror that measures and corrects the ocular and system aberrations. Because of the limitation on the current deformable mirror technologies, the amount of real-time ocular-aberration compensation is restricted and small in the previous AO-OCT instruments. In this instrument, we proposed to add an optical apparatus to correct the spectacle aberrations of the patients such as myopia, hyperopia and astigmatism. This eliminated the tedious process of the trial lenses in clinical imaging. Different amount of spectacle aberration compensation was achieved by motorized stages and automated with the AO computer for ease of clinical use. In addition, the compact AO-OCT was optimized to have minimum system aberrations to reduce AO registration errors and improve AO performance.

  2. MONSTIR II: A 32-channel, multispectral, time-resolved optical tomography system for neonatal brain imaging

    SciTech Connect (OSTI)

    Cooper, Robert J., E-mail: robert.cooper@ucl.ac.uk; Magee, Elliott; Everdell, Nick; Magazov, Salavat; Varela, Marta; Airantzis, Dimitrios; Gibson, Adam P.; Hebden, Jeremy C. [Biomedical Optics Research Laboratory, Department of Medical Physics and Bioengineering, University College London, London WC1E 6BT (United Kingdom)

    2014-05-15T23:59:59.000Z

    We detail the design, construction and performance of the second generation UCL time-resolved optical tomography system, known as MONSTIR II. Intended primarily for the study of the newborn brain, the system employs 32 source fibres that sequentially transmit picosecond pulses of light at any four wavelengths between 650 and 900 nm. The 32 detector channels each contain an independent photo-multiplier tube and temporally correlated photon-counting electronics that allow the photon transit time between each source and each detector position to be measured with high temporal resolution. The system's response time, temporal stability, cross-talk, and spectral characteristics are reported. The efficacy of MONSTIR II is demonstrated by performing multi-spectral imaging of a simple phantom.

  3. Digital Radiography and Computed Tomography Project -- Fully Integrated Linear Detector ArrayStatus Report

    SciTech Connect (OSTI)

    Tim Roney; Robert Seifert; Bob Pink; Mike Smith

    2011-09-01T23:59:59.000Z

    The field-portable Digital Radiography and Computed Tomography (DRCT) x-ray inspection systems developed for the Project Manager for NonStockpile Chemical Materiel (PMNSCM) over the past 13 years have used linear diode detector arrays from two manufacturers; Thomson and Thales. These two manufacturers no longer produce this type of detector. In the interest of insuring the long term viability of the portable DRCT single munitions inspection systems and to improve the imaging capabilities, this project has been investigating improved, commercially available detectors. During FY-10, detectors were evaluated and one in particular, manufactured by Detection Technologies (DT), Inc, was acquired for possible integration into the DRCT systems. The remainder of this report describes the work performed in FY-11 to complete evaluations and fully integrate the detector onto a representative DRCT platform.

  4. Low Temperature Age Hardening in U-13 at.% Nb: An Atom Probe Tomography Study

    SciTech Connect (OSTI)

    Clarke, A. J. [Los Alamos National Laboratory (LANL); Field, R. D. [Los Alamos National Laboratory (LANL); Hackenberg, R. E, [Los Alamos National Laboratory (LANL); Thoma, D. J. [Los Alamos National Laboratory (LANL); Brown, D. W. [Los Alamos National Laboratory (LANL); Teter, D. F. [Los Alamos National Laboratory (LANL); Miller, Michael K [ORNL; Russell, Kaye F [ORNL; Edmonds, D. V. [University of Leeds, UK; Beverini, G. [University of Leeds, UK

    2009-01-01T23:59:59.000Z

    Low temperature aging (<350 C) of U-13 at.% Nb martensite results in increased strength levels accompanied by significant ductility loss. To determine the decomposition mechanism(s) responsible for these mechanical property changes, atom probe tomography was used to examine the niobium and impurity distributions after aging at 200 or 300 C for times ranging from 2 h to 70 days. No patterns of niobium or impurity atoms were observed that would indicate segregation to the martensitic twin interfaces, making this hardening mechanism unlikely. Phase separation into roughly equiaxed regions of high and low niobium concentration was clearly observed after aging at 300 C for 70 days. However, only subtle niobium concentration changes were observed after aging at 200 C relative to the as-quenched condition, indicating that conventional phase separation is an unlikely explanation for the dramatic mechanical property changes at 200 C. Therefore, consideration of aging mechanisms other than segregation and phase separation may be warranted.

  5. Atomic-scale characterization of germanium isotopic multilayers by atom probe tomography

    SciTech Connect (OSTI)

    Shimizu, Y.; Takamizawa, H.; Toyama, T.; Inoue, K.; Nagai, Y. [Oarai Center, Institute for Materials Research, Tohoku University, 2145-2 Narita, Oarai, Ibaraki 311-1313 (Japan); Kawamura, Y.; Uematsu, M.; Itoh, K. M. [School of Fundamental Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522 (Japan); Haller, E. E. [University of California at Berkeley and Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720 (United States)

    2013-01-14T23:59:59.000Z

    We report comparison of the interfacial sharpness characterization of germanium (Ge) isotopic multilayers between laser-assisted atom probe tomography (APT) and secondary ion mass spectrometry (SIMS). An alternating stack of 8-nm-thick naturally available Ge layers and 8-nm-thick isotopically enriched {sup 70}Ge layers was prepared on a Ge(100) substrate by molecular beam epitaxy. The APT mass spectra consist of clearly resolved peaks of five stable Ge isotopes ({sup 70}Ge, {sup 72}Ge, {sup 73}Ge, {sup 74}Ge, and {sup 76}Ge). The degree of intermixing at the interfaces between adjacent layers was determined by APT to be around 0.8 {+-} 0.1 nm which was much sharper than that obtained by SIMS.

  6. Ultrasonic tomography for in-process measurements of temperature in a multi-phase medium

    DOE Patents [OSTI]

    Beller, L.S.

    1993-01-26T23:59:59.000Z

    A method and apparatus are described for the in-process measurement of internal particulate temperature utilizing ultrasonic tomography techniques to determine the speed of sound through a specimen material. Ultrasonic pulses are transmitted through a material, which can be a multi-phase material, over known flight paths and the ultrasonic pulse transit times through all sectors of the specimen are measured to determine the speed of sound. The speed of sound being a function of temperature, it is possible to establish the correlation between speed of sound and temperature, throughout a cross-section of the material, which correlation is programmed into a computer to provide for a continuous in-process measurement of temperature throughout the specimen.

  7. Thermoacoustic tomography with detectors on an open curve: an efficient reconstruction algorithm

    E-Print Network [OSTI]

    Kunyansky, Leonid

    2008-01-01T23:59:59.000Z

    Practical applications of thermoacoustic tomography require numerical inversion of the spherical mean Radon transform with the centers of integration spheres occupying an open surface. Solution of this problem is needed (both in 2-D and 3-D) because frequently the region of interest cannot be completely surrounded by the detectors, as it happens, for example, in breast imaging. We present an efficient numerical algorithm for solving this problem in 2-D (similar methods are applicable in the 3-D case). Our method is based on the numerical approximation of plane waves by certain single layer potentials related to the acquisition geometry. After the densities of these potentials have been precomputed, each subsequent image reconstruction has the complexity of the regular filtration backprojection algorithm for the classical Radon transform. The peformance of the method is demonstrated in several numerical examples: one can see that the algorithm produces very accurate reconstructions if the data are accurate and...

  8. X-ray tomography system to investigate granular materials during mechanical loading

    E-Print Network [OSTI]

    Athanasios G Athanassiadis; Patrick J. La Rivičre; Emil Sidky; Charles Pelizzari; Xiaochuan Pan; Heinrich M. Jaeger

    2014-07-28T23:59:59.000Z

    We integrate a small and portable medical x-ray device with mechanical testing equipment to enable in-situ, non-invasive measurements of a granular material's response to mechanical loading. We employ an orthopedic C-arm as the x-ray source and detector to image samples mounted in the materials tester. We discuss the design of a custom rotation stage, which allows for sample rotation and tomographic reconstruction under applied compressive stress. We then discuss the calibration of the system for 3d computed tomography, as well as the subsequent image reconstruction process. Using this system to reconstruct packings of 3d-printed particles, we resolve packing features with 0.52 mm resolution in a (60 mm)$^3$ field of view. By analyzing the performance bounds of the system, we demonstrate that the reconstructions exhibit only moderate noise.

  9. Stabilizing dual-energy X-ray computed tomography reconstructions using patch-based regularization

    E-Print Network [OSTI]

    Tracey, Brian H

    2014-01-01T23:59:59.000Z

    Recent years have seen growing interest in exploiting dual- and multi-energy measurements in computed tomography (CT) in order to characterize material properties as well as object shape. Material characterization is performed by decomposing the scene into constitutive basis functions, such as Compton scatter and photoelectric absorption functions. While well motivated physically, the joint recovery of the spatial distribution of photoelectric and Compton properties is severely complicated by the fact that the data are several orders of magnitude more sensitive to Compton scatter coefficients than to photoelectric absorption, so small errors in Compton estimates can create large artifacts in the photoelectric estimate. To address these issues, we propose a model-based iterative approach which uses patch-based regularization terms to stabilize inversion of photoelectric coefficients, and solve the resulting problem though use of computationally attractive Alternating Direction Method of Multipliers (ADMM) solu...

  10. A Fast local Reconstruction algorithm by selective backprojection for Low-Dose in Dental Computed Tomography

    E-Print Network [OSTI]

    Bin, Yan; Yu, Han; Feng, Zhang; Chao, Wang Xian; Lei, Li

    2013-01-01T23:59:59.000Z

    High radiation dose in computed tomography (CT) scans increases the lifetime risk of cancer, which become a major clinical concern. The backprojection-filtration (BPF) algorithm could reduce radiation dose by reconstructing images from truncated data in a short scan. In dental CT, it could reduce radiation dose for the teeth by using the projection acquired in a short scan, and could avoid irradiation to other part by using truncated projection. However, the limit of integration for backprojection varies per PI-line, resulting in low calculation efficiency and poor parallel performance. Recently, a tent BPF (T-BPF) has been proposed to improve calculation efficiency by rearranging projection. However, the memory-consuming data rebinning process is included. Accordingly, the chose-BPF (C-BPF) algorithm is proposed in this paper. In this algorithm, the derivative of projection is backprojected to the points whose x coordinate is less than that of the source focal spot to obtain the differentiated backprojection...

  11. Determination of Diffusion Profiles in Altered Wellbore Cement Using X-ray Computed Tomography Methods

    SciTech Connect (OSTI)

    Mason, Harris E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Walsh, Stuart D. C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); DuFrane, Wyatt L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Carroll, Susan A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-06-17T23:59:59.000Z

    The development of accurate, predictive models for use in determining wellbore integrity requires detailed information about the chemical and mechanical changes occurring in hardened Portland cements. X-ray computed tomography (XRCT) provides a method that can nondestructively probe these changes in three dimensions. Here, we describe a method for extracting subvoxel mineralogical and chemical information from synchrotron XRCT images by combining advanced image segmentation with geochemical models of cement alteration. The method relies on determining “effective linear activity coefficients” (ELAC) for the white light source to generate calibration curves that relate the image grayscales to material composition. The resulting data set supports the modeling of cement alteration by CO2-rich brine with discrete increases in calcium concentration at reaction boundaries. The results of these XRCT analyses can be used to further improve coupled geochemical and mechanical models of cement alteration in the wellbore environment.

  12. Functional optoacoustic neuro-tomography (FONT) for whole-brain monitoring of calcium indicators

    E-Print Network [OSTI]

    Sela, Gali; Deán-Ben, X Luís; Kneipp, Moritz; Ntziachristos, Vasilis; Shoham, Shy; Westmeyer, Gil G; Razansky, Daniel

    2015-01-01T23:59:59.000Z

    Non-invasive observation of spatiotemporal neural activity of large neural populations distributed over entire brains is a longstanding goal of neuroscience. We developed a real-time volumetric and multispectral optoacoustic tomography platform for imaging of neural activation deep in scattering brains. The system can record 100 volumetric frames per second across a 200mm3 field of view and spatial resolutions below 70um. Experiments performed in immobilized and freely swimming larvae and in adult zebrafish brains demonstrate, for the first time, the fundamental ability to optoacoustically track neural calcium dynamics in animals labeled with genetically encoded calcium indicator GCaMP5G, while overcoming the longstanding penetration barrier of optical imaging in scattering brains. The newly developed platform offers unprecedented capabilities for functional whole-brain observations of fast calcium dynamics; in combination with optoacoustics' well-established capacity in resolving vascular hemodynamics, it co...

  13. X-ray tomography system to investigate granular materials during mechanical loading

    SciTech Connect (OSTI)

    Athanassiadis, Athanasios G. [James Franck Institute and Department of Physics, The University of Chicago, Chicago, Illinois 60637 (United States); Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); La Rivičre, Patrick J.; Sidky, Emil; Pan, Xiaochuan [Department of Radiology, The University of Chicago, Chicago, Illinois 60637 (United States); Pelizzari, Charles [Department of Radiation and Cellular Oncology, The University of Chicago, Chicago, Illinois 60637 (United States); Jaeger, Heinrich M., E-mail: h-jaeger@uchicago.edu [James Franck Institute and Department of Physics, The University of Chicago, Chicago, Illinois 60637 (United States)

    2014-08-15T23:59:59.000Z

    We integrate a small and portable medical x-ray device with mechanical testing equipment to enable in situ, non-invasive measurements of a granular material's response to mechanical loading. We employ an orthopedic C-arm as the x-ray source and detector to image samples mounted in the materials tester. We discuss the design of a custom rotation stage, which allows for sample rotation and tomographic reconstruction under applied compressive stress. We then discuss the calibration of the system for 3D computed tomography, as well as the subsequent image reconstruction process. Using this system to reconstruct packings of 3D-printed particles, we resolve packing features with 0.52?mm resolution in a (60 mm){sup 3} field of view. By analyzing the performance bounds of the system, we demonstrate that the reconstructions exhibit only moderate noise.

  14. Using electrokinetic phenomena and electrical resistance tomography to characterize the movement of subsurface fluids

    DOE Patents [OSTI]

    Ramirez, A.L.; Cooper, J.F.; Daily, W.D.

    1996-02-27T23:59:59.000Z

    This invention relates generally to the remote detections of subsurface liquid contaminants using in combination a geophysical technique known as ERT and an EKS. Electrokinetic transport is used to enhance the ability of electrical resistance tomography (ERT) to detect position and movement of subsurface contaminant liquids, particles or ions. ERT images alone are difficult to interpret because of natural inhomogeneities in soil composition and electrical properties. By subtracting two or more ERT images obtained before and after field induced movement, a high contrast image of a plume of distinct electrokinetic properties can be seen. The invention is applicable to important subsurface characterization problems including, as examples, (1) detection of liquid-saturated plumes of contaminants such as those associated with leaks from underground storage tanks containing hazardous concentrated electrolytes, (2) detection and characterization of soils contaminated with organic pollutants such as droplets of gasoline; and (3) monitoring the progress of electrokinetic containment or clean up of underground contamination. 1 fig.

  15. Using electrokinetic phenomena and electrical resistance tomography to characterize the movement of subsurface fluids

    DOE Patents [OSTI]

    Ramirez, Abelardo L. (Pleasanton, CA); Cooper, John F. (Oakland, CA); Daily, William D. (Livermore, CA)

    1996-01-01T23:59:59.000Z

    This invention relates generally to the remote detections of subsurface liquid contaminants using in combination a geophysical technique known as ERT and an EKS. Electrokinetic transport is used to enhance the ability of electrical resistance tomography (ERT) to detect position and movement of subsurface contaminant liquids, particles or ions. ERT images alone are difficult to interpret because of natural inhomogeneities in soil composition and electrical properties. By subtracting two or more ERT images obtained before and after field induced movement, a high contrast image of a plume of distinct electrokinetic properties can be seen. The invention is applicable to important subsurface characterization problems including, as examples, (1) detection of liquid-saturated plumes of contaminants such as those associated with leaks from underground storage tanks containing hazardous concentrated electrolytes, (2) detection and characterization of soils contaminated with organic pollutants such as droplets of gasoline; and (3) monitoring the progress of electrokinetic containment or clean up of underground contamination.

  16. Three-dimensional architecture of hair-cell linkages as revealedby electron-microscopic tomography

    SciTech Connect (OSTI)

    Auer, Manfred; Koster, Bram; Ziese, Ulrike; Bajaj, Chandrajit; Volkmann, Niels; Wang, Da Neng; Hudspeth, A. James

    2006-07-28T23:59:59.000Z

    The senses of hearing and balance rest upon mechanoelectrical transduction by the hair bundles of hair cells in the inner ear. Located at the apical cellular surface, each hair bundle comprises several tens of stereocilia and a single kinocilium that are interconnected by extracellular proteinaceous links. Using electron-microscopic tomography of bullfrog saccular sensory epithelia, we examined the three-dimensional structures of ankle or basal links, kinociliary links, and tip links. We observed clear differences in the dimensions and appearances of the three links. We found two distinct populations of tip links suggestive of the involvement of two proteins or splice variants. We noted auxiliary links connecting the upper portions of tip links to the taller stereocilia. Tip links and auxiliary links show a tendency to adopt a globular conformation when disconnected from the membrane surface.

  17. Measurement of breast tissue composition with dual energy cone-beam computed tomography: A postmortem study

    SciTech Connect (OSTI)

    Ding Huanjun; Ducote, Justin L.; Molloi, Sabee [Department of Radiological Sciences, University of California, Irvine, California 92697 (United States)

    2013-06-15T23:59:59.000Z

    Purpose: To investigate the feasibility of a three-material compositional measurement of water, lipid, and protein content of breast tissue with dual kVp cone-beam computed tomography (CT) for diagnostic purposes. Methods: Simulations were performed on a flat panel-based computed tomography system with a dual kVp technique in order to guide the selection of experimental acquisition parameters. The expected errors induced by using the proposed calibration materials were also estimated by simulation. Twenty pairs of postmortem breast samples were imaged with a flat-panel based dual kVp cone-beam CT system, followed by image-based material decomposition using calibration data obtained from a three-material phantom consisting of water, vegetable oil, and polyoxymethylene plastic. The tissue samples were then chemically decomposed into their respective water, lipid, and protein contents after imaging to allow direct comparison with data from dual energy decomposition. Results: Guided by results from simulation, the beam energies for the dual kVp cone-beam CT system were selected to be 50 and 120 kVp with the mean glandular dose divided equally between each exposure. The simulation also suggested that the use of polyoxymethylene as the calibration material for the measurement of pure protein may introduce an error of -11.0%. However, the tissue decomposition experiments, which employed a calibration phantom made out of water, oil, and polyoxymethylene, exhibited strong correlation with data from the chemical analysis. The average root-mean-square percentage error for water, lipid, and protein contents was 3.58% as compared with chemical analysis. Conclusions: The results of this study suggest that the water, lipid, and protein contents can be accurately measured using dual kVp cone-beam CT. The tissue compositional information may improve the sensitivity and specificity for breast cancer diagnosis.

  18. Time-dependent seismic tomography and its application to the Coso geothermal area, 1996-2006

    SciTech Connect (OSTI)

    Julian, B.R.; G.R. Foulger; F. Monastero

    2008-04-01T23:59:59.000Z

    Measurements of temporal changes in Earth structure are commonly determined using localearthquake tomography computer programs that invert multiple seismic-wave arrival time data sets separately and assume that any differences in the structural results arise from real temporal variations. This assumption is dangerous because the results of repeated tomography experiments would differ even if the structure did not change, simply because of variation in the seismic ray distribution caused by the natural variation in earthquake locations. Even if the source locations did not change (if only explosion data were used, for example), derived structures would inevitably differ because of observational errors. A better approach is to invert multiple data sets simultaneously, which makes it possible to determine what changes are truly required by the data. This problem is similar to that of seeking models consistent with initial assumptions, and techniques similar to the “damped least squares” method can solve it. We have developed a computer program, dtomo, that inverts multiple epochs of arrival-time measurements to determine hypocentral parameters and structural changes between epochs. We shall apply this program to data from the seismically active Coso geothermal area, California, in the near future. The permanent network operated there by the US Navy, supplemented by temporary stations, has provided excellent earthquake arrival-time data covering a span of more than a decade. Furthermore, structural change is expected in the area as a result of geothermal exploitation of the resource. We have studied the period 1996 through 2006. Our results to date using the traditional method show, for a 2-km horizontal grid spacing, an irregular strengthening with time of a negative VP/VS anomaly in the upper ~ 2 km of the reservoir. This progressive reduction in VP/VS results predominately from an increase of VS with respect to VP. Such a change is expected to result from effects of geothermal operations such as decreasing fluid pressure and the drying of argillaceous minerals such as illite.

  19. A new method for imaging nuclear threats using cosmic ray muons

    SciTech Connect (OSTI)

    Morris, C. L.; Bacon, Jeffrey; Borozdin, Konstantin; Miyadera, Haruo; Perry, John; Rose, Evan; Watson, Scott; White, Tim [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)] [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Aberle, Derek; Green, J. Andrew; McDuff, George G. [National Security Technologies, Los Alamos, NM 87544 (United States)] [National Security Technologies, Los Alamos, NM 87544 (United States); Luki?, Zarija [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)] [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Milner, Edward C. [Southern Methodist University, Dallas, TX 75205 (United States)] [Southern Methodist University, Dallas, TX 75205 (United States)

    2013-08-15T23:59:59.000Z

    Muon tomography is a technique that uses cosmic ray muons to generate three dimensional images of volumes using information contained in the Coulomb scattering of the muons. Advantages of this technique are the ability of cosmic rays to penetrate significant overburden and the absence of any additional dose delivered to subjects under study above the natural cosmic ray flux. Disadvantages include the relatively long exposure times and poor position resolution and complex algorithms needed for reconstruction. Here we demonstrate a new method for obtaining improved position resolution and statistical precision for objects with spherical symmetry.

  20. EXERCISE-INDUCED ACUTE CHANGES IN SYSTOLIC BLOOD PRESSURE DO NOT ALTER CHOROIDAL THICKNESS AS MEASURED BY A PORTABLE SPECTRAL-DOMAIN OPTICAL COHERENCE TOMOGRAPHY DEVICE

    E-Print Network [OSTI]

    Alwassia, Ahmad A.

    Purpose: To measure choroidal thickness in patients manifesting an acute change in systemic arterial blood pressure using a portable spectral-domain optical coherence tomography device (iVue).

  1. A field comparison of Fresnel zone and ray-based GPR attenuation-difference tomography for time-lapse imaging of

    E-Print Network [OSTI]

    Barrash, Warren

    A field comparison of Fresnel zone and ray-based GPR attenuation-difference tomography for time the medium. These sensitivities occupy the first Fresnel zone, account for the finite frequency nature

  2. Addressing the risks of diagnostic radiology : what should be done about the increasing use of computed tomography in the United States

    E-Print Network [OSTI]

    Eastwick, Gary (Gary A.)

    2010-01-01T23:59:59.000Z

    Computed tomography (CT) is a prominent procedure in the US with larger radiation doses than traditional radiology. CT is a powerful tool in the diagnosis of a wide variety of conditions and its use has grown quickly because ...

  3. A Parametric Level Set Approach to Simultaneous Object Identification and Background Reconstruction for Dual Energy Computed Tomography

    E-Print Network [OSTI]

    Semerci, Oguz

    2011-01-01T23:59:59.000Z

    Dual energy computerized tomography has gained great interest because of its ability to characterize the chemical composition of a material rather than simply providing relative attenuation images as in conventional tomography. The purpose of this paper is to introduce a novel polychromatic dual energy processing algorithm with an emphasis on detection and characterization of piecewise constant objects embedded in an unknown, cluttered background. Physical properties of the objects, specifically the Compton scattering and photoelectric absorption coefficients, are assumed to be known with some level of uncertainty. Our approach is based on a level-set representation of the characteristic function of the object and encompasses a number of regularization techniques for addressing both the prior information we have concerning the physical properties of the object as well as fundamental, physics-based limitations associated with our ability to jointly recover the Compton scattering and photoelectric absorption pr...

  4. Technology Transfer Success Stories, Security

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of Research and Development at NETL Muon Tomography Muon Tomography Muon Tomography technology developed at LANL to detect nuclear and other weapons of mass destruction will be...

  5. Fluorodeoxyglucose Positron Emission Tomography Response and Normal Tissue Regeneration After Stereotactic Body Radiotherapy to Liver Metastases

    SciTech Connect (OSTI)

    Stinauer, Michelle A., E-mail: Michelle.Stinauer@ucdenver.edu [Department of Radiation Oncology, University of Colorado Denver, Aurora, Colorado (United States); Diot, Quentin; Westerly, David C.; Schefter, Tracey E.; Kavanagh, Brian D. [Department of Radiation Oncology, University of Colorado Denver, Aurora, Colorado (United States)] [Department of Radiation Oncology, University of Colorado Denver, Aurora, Colorado (United States)

    2012-08-01T23:59:59.000Z

    Purpose: To characterize changes in standardized uptake value (SUV) in positron emission tomography (PET) scans and determine the pace of normal tissue regeneration after stereotactic body radiation therapy (SBRT) for solid tumor liver metastases. Methods and Materials: We reviewed records of patients with liver metastases treated with SBRT to {>=}40 Gy in 3-5 fractions. Evaluable patients had pretreatment PET and {>=}1 post-treatment PET. Each PET/CT scan was fused to the planning computed tomography (CT) scan. The maximum SUV (SUV{sub max}) for each lesion and the total liver volume were measured on each PET/CT scan. Maximum SUV levels before and after SBRT were recorded. Results: Twenty-seven patients with 35 treated liver lesions were studied. The median follow-up was 15.7 months (range, 1.5-38.4 mo), with 5 PET scans per patient (range, 2-14). Exponential decay curve fitting (r=0.97) showed that SUV{sub max} declined to a plateau of 3.1 for controlled lesions at 5 months after SBRT. The estimated SUV{sub max} decay half-time was 2.0 months. The SUV{sub max} in controlled lesions fluctuated up to 4.2 during follow-up and later declined; this level is close to 2 standard deviations above the mean normal liver SUV{sub max} (4.01). A failure cutoff of SUV{sub max} {>=}6 is twice the calculated plateau SUV{sub max} of controlled lesions. Parenchymal liver volume decreased by 20% at 3-6 months and regenerated to a new baseline level approximately 10% below the pretreatment level at 12 months. Conclusions: Maximum SUV decreases over the first months after SBRT to plateau at 3.1, similar to the median SUV{sub max} of normal livers. Transient moderate increases in SUV{sub max} may be observed after SBRT. We propose a cutoff SUV{sub max} {>=}6, twice the baseline normal liver SUV{sub max}, to score local failure by PET criteria. Post-SBRT values between 4 and 6 would be suspicious for local tumor persistence or recurrence. The volume of normal liver reached nadir 3-6 months after SBRT and regenerated within the next 6 months.

  6. High-speed digitization readout of silicon photomultipliers for time of flight positron emission tomography

    SciTech Connect (OSTI)

    Ronzhin, A.; Los, S.; Martens, M.; Ramberg, E.; /Fermilab; Kim, H.; Chen, C.; Kao, C.; /Chicago U.; Niessen, K.; /SUNY, Buffalo; Zatserklyaniy, A.; /Puerto Rico U., Mayaguez; Mazzillo, M.; Carbone, B.; /SGS Thomson, Catania

    2011-02-01T23:59:59.000Z

    We report on work to develop a system with about 100 picoseconds (ps) time resolution for time of flight positron emission tomography [TOF-PET]. The chosen photo detectors for the study were Silicon Photomultipliers (SiPM's). This study was based on extensive experience in studying timing properties of SiPM's. The readout of these devices used the commercial high speed digitizer DRS4. We applied different algorithms to get the best time resolution of 155 ps Guassian (sigma) for a LYSO crystal coupled to a SiPM. We consider the work as a first step in building a prototype TOF-PET module. The field of positron-emission-tomography (PET) has been rapidly developing. But there are significant limitations in how well current PET scanners can reconstruct images, related to how fast data can be acquired, how much volume they can image, and the spatial and temporal resolution of the generated photons. Typical modern scanners now include multiple rings of detectors, which can image a large volume of the patient. In this type of scanner, one can treat each ring as a separate detector and require coincidences only within the ring, or treat the entire region viewed by the scanner as a single 3 dimensional volume. This 3d technique has significantly better sensitivity since more photon pair trajectories are accepted. However, the scattering of photons within the volume of the patient, and the effect of random coincidences limits the technique. The advent of sub-nanosecond timing resolution detectors means that there is potentially much better rejection of scattered photon events and random coincidence events in the 3D technique. In addition, if the timing is good enough, then the origin of photons pairs can be determined better, resulting in improved spatial resolution - so called 'Time-of-Flight' PET, or TOF-PET. Currently a lot of activity has occurred in applications of SiPMs for TOF-PET. This is due to the devices very good time resolution, low profile, lack of high voltage needed, and their non-sensitivity to magnetic fields. While investigations into this technique have begun elsewhere, we feel that the extensive SiPM characterization and data acquisition expertise of Fermilab, and the historical in-depth research of PET imaging at University of Chicago will combine to make significant strides in this field. We also benefit by a working relationship with the SiPM producer STMicroelectronics (STM).

  7. Organ doses for reference adult male and female undergoing computed tomography estimated by Monte Carlo simulations

    SciTech Connect (OSTI)

    Lee, Choonsik; Kim, Kwang Pyo; Long, Daniel; Fisher, Ryan; Tien, Chris; Simon, Steven L.; Bouville, Andre; Bolch, Wesley E. [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institute of Health, Bethesda, Maryland 20852 (United States); Department of Nuclear Engineering, Kyung Hee University, Yongin 446-701 (Korea, Republic of); Department of Nuclear and Radiological Engineering, University of Florida, Gainesville, Florida 32611 (United States); Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institute of Health, Bethesda, Maryland 20852 (United States); Department of Nuclear and Radiological Engineering, University of Florida, Gainesville, Florida 32611 (United States)

    2011-03-15T23:59:59.000Z

    Purpose: To develop a computed tomography (CT) organ dose estimation method designed to readily provide organ doses in a reference adult male and female for different scan ranges to investigate the degree to which existing commercial programs can reasonably match organ doses defined in these more anatomically realistic adult hybrid phantomsMethods: The x-ray fan beam in the SOMATOM Sensation 16 multidetector CT scanner was simulated within the Monte Carlo radiation transport code MCNPX2.6. The simulated CT scanner model was validated through comparison with experimentally measured lateral free-in-air dose profiles and computed tomography dose index (CTDI) values. The reference adult male and female hybrid phantoms were coupled with the established CT scanner model following arm removal to simulate clinical head and other body region scans. A set of organ dose matrices were calculated for a series of consecutive axial scans ranging from the top of the head to the bottom of the phantoms with a beam thickness of 10 mm and the tube potentials of 80, 100, and 120 kVp. The organ doses for head, chest, and abdomen/pelvis examinations were calculated based on the organ dose matrices and compared to those obtained from two commercial programs, CT-EXPO and CTDOSIMETRY. Organ dose calculations were repeated for an adult stylized phantom by using the same simulation method used for the adult hybrid phantom. Results: Comparisons of both lateral free-in-air dose profiles and CTDI values through experimental measurement with the Monte Carlo simulations showed good agreement to within 9%. Organ doses for head, chest, and abdomen/pelvis scans reported in the commercial programs exceeded those from the Monte Carlo calculations in both the hybrid and stylized phantoms in this study, sometimes by orders of magnitude. Conclusions: The organ dose estimation method and dose matrices established in this study readily provides organ doses for a reference adult male and female for different CT scan ranges and technical parameters. Organ doses from existing commercial programs do not reasonably match organ doses calculated for the hybrid phantoms due to differences in phantom anatomy, as well as differences in organ dose scaling parameters. The organ dose matrices developed in this study will be extended to cover different technical parameters, CT scanner models, and various age groups.

  8. Radiation doses in cone-beam breast computed tomography: A Monte Carlo simulation study

    SciTech Connect (OSTI)

    Yi Ying; Lai, Chao-Jen; Han Tao; Zhong Yuncheng; Shen Youtao; Liu Xinming; Ge Shuaiping; You Zhicheng; Wang Tianpeng; Shaw, Chris C. [Department of Imaging Physics, University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States)

    2011-02-15T23:59:59.000Z

    Purpose: In this article, we describe a method to estimate the spatial dose variation, average dose and mean glandular dose (MGD) for a real breast using Monte Carlo simulation based on cone beam breast computed tomography (CBBCT) images. We present and discuss the dose estimation results for 19 mastectomy breast specimens, 4 homogeneous breast models, 6 ellipsoidal phantoms, and 6 cylindrical phantoms. Methods: To validate the Monte Carlo method for dose estimation in CBBCT, we compared the Monte Carlo dose estimates with the thermoluminescent dosimeter measurements at various radial positions in two polycarbonate cylinders (11- and 15-cm in diameter). Cone-beam computed tomography (CBCT) images of 19 mastectomy breast specimens, obtained with a bench-top experimental scanner, were segmented and used to construct 19 structured breast models. Monte Carlo simulation of CBBCT with these models was performed and used to estimate the point doses, average doses, and mean glandular doses for unit open air exposure at the iso-center. Mass based glandularity values were computed and used to investigate their effects on the average doses as well as the mean glandular doses. Average doses for 4 homogeneous breast models were estimated and compared to those of the corresponding structured breast models to investigate the effect of tissue structures. Average doses for ellipsoidal and cylindrical digital phantoms of identical diameter and height were also estimated for various glandularity values and compared with those for the structured breast models. Results: The absorbed dose maps for structured breast models show that doses in the glandular tissue were higher than those in the nearby adipose tissue. Estimated average doses for the homogeneous breast models were almost identical to those for the structured breast models (p=1). Normalized average doses estimated for the ellipsoidal phantoms were similar to those for the structured breast models (root mean square (rms) percentage difference=1.7%; p=0.01), whereas those for the cylindrical phantoms were significantly lower (rms percentage difference=7.7%; p<0.01). Normalized MGDs were found to decrease with increasing glandularity. Conclusions: Our results indicate that it is sufficient to use homogeneous breast models derived from CBCT generated structured breast models to estimate the average dose. This investigation also shows that ellipsoidal digital phantoms of similar dimensions (diameter and height) and glandularity to actual breasts may be used to represent a real breast to estimate the average breast dose with Monte Carlo simulation. We have also successfully demonstrated the use of structured breast models to estimate the true MGDs and shown that the normalized MGDs decreased with the glandularity as previously reported by other researchers for CBBCT or mammography.

  9. Tomography of one and two qubit states and factorisation of the Wigner distribution in prime power dimensions

    E-Print Network [OSTI]

    Thomas Durt

    2006-04-17T23:59:59.000Z

    We study different techniques that allow us to gain complete knowledge about an unknown quantum state, e.g. to perform full tomography of this state. We focus on two apparently simple cases, full tomography of one and two qubit systems. We analyze and compare those techniques according to two figures of merit. Our first criterion is the minimisation of the redundancy of the data acquired during the tomographic process. In the case of two-qubits tomography, we also analyze this process from the point of view of factorisability, so to say we analyze the possibility to realise the tomographic process through local operations and classical communications between local observers. This brings us naturally to study the possibility to factorize the (discrete) Wigner distribution of a composite system into the product of local Wigner distributions. The discrete Heisenberg-Weyl group is an essential ingredient of our approach. Possible extensions of our results to higher dimensions are discussed in the last section and in the conclusions.

  10. Volume-Based Parameters of {sup 18}F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Improve Disease Recurrence Prediction in Postmastectomy Breast Cancer Patients With 1 to 3 Positive Axillary Lymph Nodes

    SciTech Connect (OSTI)

    Nakajima, Naomi, E-mail: haruhi0321@gmail.com [Department of Radiation Oncology, National Hospital Organization Shikoku Cancer Center, Ehime (Japan); Department of Radiology, Ehime University, Ehime (Japan); Kataoka, Masaaki [Department of Radiation Oncology, National Hospital Organization Shikoku Cancer Center, Ehime (Japan); Sugawara, Yoshifumi [Department of Diagnostic Radiology, National Hospital Organization Shikoku Cancer Center, Ehime (Japan); Ochi, Takashi [Department of Radiology, Ehime University, Ehime (Japan); Kiyoto, Sachiko; Ohsumi, Shozo [Department of Breast Oncology, National Hospital Organization Shikoku Cancer Center, Ehime (Japan); Mochizuki, Teruhito [Department of Radiology, Ehime University, Ehime (Japan)

    2013-11-15T23:59:59.000Z

    Purpose: To determine whether volume-based parameters on pretreatment {sup 18}F-fluorodeoxyglucose positron emission tomography/computed tomography in breast cancer patients treated with mastectomy without adjuvant radiation therapy are predictive of recurrence. Methods and Materials: We retrospectively analyzed 93 patients with 1 to 3 positive axillary nodes after surgery, who were studied with {sup 18}F-fluorodeoxyglucose positron emission tomography/computed tomography for initial staging. We evaluated the relationship between positron emission tomography parameters, including the maximum standardized uptake value, metabolic tumor volume (MTV), and total lesion glycolysis (TLG), and clinical outcomes. Results: The median follow-up duration was 45 months. Recurrence was observed in 11 patients. Metabolic tumor volume and TLG were significantly related to tumor size, number of involved nodes, nodal ratio, nuclear grade, estrogen receptor (ER) status, and triple negativity (TN) (all P values were <.05). In receiver operating characteristic curve analysis, MTV and TLG showed better predictive performance than tumor size, ER status, or TN (area under the curve: 0.85, 0.86, 0.79, 0.74, and 0.74, respectively). On multivariate analysis, MTV was an independent prognostic factor of locoregional recurrence-free survival (hazard ratio 34.42, 95% confidence interval 3.94-882.71, P=.0008) and disease-free survival (DFS) (hazard ratio 13.92, 95% confidence interval 2.65-103.78, P=.0018). The 3-year DFS rate was 93.8% for the lower MTV group (<53.1; n=85) and 25.0% for the higher MTV group (?53.1; n=8; P<.0001, log–rank test). The 3-year DFS rate for patients with both ER-positive status and MTV <53.1 was 98.2%; and for those with ER-negative status and MTV ?53.1 it was 25.0% (P<.0001). Conclusions: Volume-based parameters improve recurrence prediction in postmastectomy breast cancer patients with 1 to 3 positive nodes. The addition of MTV to ER status or TN has potential benefits to identify a subgroup at higher risk for recurrence.

  11. Atom Probe Tomography Examination of Carbon Redistribution in Quenched and Tempered 4340 Steel

    SciTech Connect (OSTI)

    Clarke, Amy J. [Los Alamos National Laboratory; Miller, Michael K. [ORNL; Alexander, David J. [Los Alamos National Laboratory; Field, Robert D. [Los Alamos National Laboratory; Clarke, Kester D. [Los Alamos National Laboratory

    2012-08-07T23:59:59.000Z

    Quenching and tempering produces a wide range of mechanical properties in medium carbon, low alloyed steels - Study fragmentation behavior as a function of heat-treatment. Subtle microstructural changes accompany the mechanical property changes that result from quenching and tempering - Characterize the location and distribution of carbon and alloying elements in the microstructure using atom probe tomography (APT). Perform complementary transmission electron microscopy (TEM). Tempering influences the mechanical properties and fragmentation of quenched 4340 (hemi-shaped samples). APT revealed carbon-enriched features that contain a maximum of {approx}12-14 at.% carbon after quenching to RT (the level of carbon is perhaps associated with the extent of autotempering). TEM confirmed the presence of twinned martensite and indicates {var_epsilon} ({eta}) transition carbides after oil quenching to RT. Tempering at 325 C resulted in carbon-enriched plates (> 25 at.% C) with no significant element partitioning (transition carbides?). Tempering at 450 C and 575 C resulted in cementite ({approx} 25 at.% C) during late stage tempering; Cr, Mn, Mo partitioned to cementite and Si partitioned to ferrite. Tempering at 575 C resulted in P segregation at cementite interfaces and the formation of Cottrell atmospheres.

  12. Combined 3D PET and Optical Projection Tomography Techniques for Plant Root Phenotyping

    E-Print Network [OSTI]

    Wang, Qiang; Mathews, Aswin J; Li, Ke; Topp, Christopher; O'Sullivan, Joseph A; Tai, Yuan-Chuan

    2015-01-01T23:59:59.000Z

    New imaging techniques are in great demand for investigating underground plant roots systems which play an important role in crop production. Compared with other non-destructive imaging modalities, PET can image plant roots in natural soil and produce dynamic 3D functional images which reveal the temporal dynamics of plant-environment interactions. In this study, we combined PET with optical projection tomography (OPT) to evaluate its potential for plant root phenotyping. We used a dedicated high resolution plant PET imager that has a 14 cm transaxial and 10 cm axial field of views, and multi-bed imaging capability. The image resolution is around 1.25 mm using ML-EM reconstruction algorithm. B73 inbred maize seeds were germinated and then grown in a sealed jar with transparent gel-based media. PET scanning started on the day when the first green leaf appeared, and was carried out once a day for 5 days. Each morning, around 10 mCi of 11CO2 was administrated into a custom built plant labeling chamber. After 10 ...

  13. Low background high efficiency radiocesium detection system based on positron emission tomography technology

    SciTech Connect (OSTI)

    Yamamoto, Seiichi; Ogata, Yoshimune [Department of Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine, 1-1-20 Daiko-Minami, Higashi-ku, Nagoya 461-8673 (Japan)] [Department of Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine, 1-1-20 Daiko-Minami, Higashi-ku, Nagoya 461-8673 (Japan)

    2013-09-15T23:59:59.000Z

    After the 2011 nuclear power plant accident at Fukushima, radiocesium contamination in food became a serious concern in Japan. However, low background and high efficiency radiocesium detectors are expensive and huge, including semiconductor germanium detectors. To solve this problem, we developed a radiocesium detector by employing positron emission tomography (PET) technology. Because {sup 134}Cs emits two gamma photons (795 and 605 keV) within 5 ps, they can selectively be measured with coincidence. Such major environmental gamma photons as {sup 40}K (1.46 MeV) are single photon emitters and a coincidence measurement reduces the detection limit of radiocesium detectors. We arranged eight sets of Bi{sub 4}Ge{sub 3}O{sub 12} (BGO) scintillation detectors in double rings (four for each ring) and measured the coincidence between these detectors using PET data acquisition system. A 50 × 50 × 30 mm BGO was optically coupled to a 2 in. square photomultiplier tube (PMT). By measuring the coincidence, we eliminated most single gamma photons from the energy distribution and only detected those from {sup 134}Cs at an average efficiency of 12%. The minimum detectable concentration of the system for the 100 s acquisition time is less than half of the food monitor requirements in Japan (25 Bq/kg). These results show that the developed radiocesium detector based on PET technology is promising to detect low level radiocesium.

  14. EELS Spectrum Imaging and Tomography Studies of Simulated Nuclear Waste Glasses

    SciTech Connect (OSTI)

    Yang, Guang; Saghi, Zineb; Xu, Xiaojing; Hand, Russell; Moebus, Guenter [Engineering Materials, The University of Sheffield, Sir Robert Hadfield Building, Mappin Street, Sheffield, S1 3JD (United Kingdom)

    2007-07-01T23:59:59.000Z

    Electron energy loss spectroscopy (EELS) fine structure is a powerful technique for analyzing oxidation levels of rare-earth oxides and coordination numbers in glasses and ceramics, especially for boron. To exploit the unique advantage of EELS over x-ray absorption spectroscopy (XAS)/x-ray absorption near edge structure (XANES), namely nm-scale spatial resolution, EELS spectrum imaging across precipitates in glasses has been employed to detect lateral changes of EELS fine structure. Alkali borosilicate (ABS) glasses doped with Cr{sub 2}O{sub 3}, CeO{sub 2} and ZrO{sub 2} or Fe{sub 2}O{sub 3} were melted to simulate high level radionuclide immobilization glasses. Precipitates with diameter in the range of {approx}20 nm to {approx}500 nm were found homogeneously distributed in the glasses. Ce valence was found to be mainly +3 in the glass matrix, and +4 in crystalline precipitates, while some amorphous particles show +3 as well. Another powerful TEM technique for the analysis of glass-nano-composites is electron tomography, as it is up to now the only technique for the three-dimensional reconstruction of nano-particles. A 3D reconstructed nuclear waste glass is presented in this paper by using a tilt series of ADF STEM images covering a glass fragment of {approx}3{mu}m field of view containing several tens of nano-particles distributed throughout its volume. (authors)

  15. Iterative reconstruction using a Monte Carlo based system transfer matrix for dedicated breast positron emission tomography

    SciTech Connect (OSTI)

    Saha, Krishnendu [Ohio Medical Physics Consulting, Dublin, Ohio 43017 (United States); Straus, Kenneth J.; Glick, Stephen J. [Department of Radiology, University of Massachusetts Medical School, Worcester, Massachusetts 01655 (United States); Chen, Yu. [Department of Radiation Oncology, Columbia University, New York, New York 10032 (United States)

    2014-08-28T23:59:59.000Z

    To maximize sensitivity, it is desirable that ring Positron Emission Tomography (PET) systems dedicated for imaging the breast have a small bore. Unfortunately, due to parallax error this causes substantial degradation in spatial resolution for objects near the periphery of the breast. In this work, a framework for computing and incorporating an accurate system matrix into iterative reconstruction is presented in an effort to reduce spatial resolution degradation towards the periphery of the breast. The GATE Monte Carlo Simulation software was utilized to accurately model the system matrix for a breast PET system. A strategy for increasing the count statistics in the system matrix computation and for reducing the system element storage space was used by calculating only a subset of matrix elements and then estimating the rest of the elements by using the geometric symmetry of the cylindrical scanner. To implement this strategy, polar voxel basis functions were used to represent the object, resulting in a block-circulant system matrix. Simulation studies using a breast PET scanner model with ring geometry demonstrated improved contrast at 45% reduced noise level and 1.5 to 3 times resolution performance improvement when compared to MLEM reconstruction using a simple line-integral model. The GATE based system matrix reconstruction technique promises to improve resolution and noise performance and reduce image distortion at FOV periphery compared to line-integral based system matrix reconstruction.

  16. Determination of the spatial characteristics of an RF electrodeless discharge by the method of emission tomography

    SciTech Connect (OSTI)

    Denisova, N. V. [Russian Academy of Sciences, Institute of Theoretical and Applied Mechanics, Siberian Division (Russian Federation); Revalde, G.; Skudra, A. [University of Latvia, Institute of Atomic physics and Spectroscopy (Latvia)

    2006-11-15T23:59:59.000Z

    The spatial distribution of the density of mercury atoms in the 7{sup 3}S state in a spherical RF electrode-less gas-discharge lamp is reconstructed by the method of emission tomography. The local values of the corresponding emission coefficients, which are proportional to the density of mercury atoms in the 7{sup 3}S state, are determined from integral (over the plasma volume) measurements of the lamp radiation at a wavelength of 546.1 nm with the help of an algorithm based on the maximum entropy method. The results obtained show that, for all of the operating modes under study, the profile of the density of mercury atoms in the 7{sup 3}S state has a minimum in the center of the lamp and a maximum near its wall. At a generator current of 100 mA and cold-spot temperature of 41 deg. C, the density of mercury atoms in the 7{sup 3}S state is observed to drop substantially both in the center of the lamp and near its wall, the density in the center being reduced to almost zero. An explanation of this phenomenon is proposed.

  17. Relationship of brain imaging with radionuclides and with x-ray computed tomography

    SciTech Connect (OSTI)

    Kuhl, D.E.

    1981-03-03T23:59:59.000Z

    Because of high sensitivity and specificity for altered local cerebral structure, x-ray computed tomography (CT) is the preferred initial diagnostic imaging study under most circumstances when cerebral disease is suspected. CT has no competitor for detecting fresh intracerebral hemorrhage. Radionuclide imaging (RN) scan is preferred when relative perfusion is to be assessed, in patients allergic to contrast media, and when an adequate CT study is not technically possible. (RN) plays an important complementary role to CT, especially for patients suspected of subacute or chronic subdura hematoma, cerebral infarction, arteriovenous malformations, meningitis, encephalitis, normal pressure hydrocephalus, or when CT findings are inconclusive. When CT is not available, RN serves as a good screening study for suspected cerebral tumor, infection, recent infarction, arteriovenous malformation, and chronic subdural hematoma. Future improvement in radionuclide imaging by means of emission composition potential. The compound plating approacl threshold for all the investigated transistors and fast neutron spectra lies within the raal. The value of the potential slightly changes with the coordinate change in this region, i.e. the charge on a collecting electrode is not practically guided up to a certain moment of time during the movement of nonequilibrium carriers.

  18. Data fusion in X-ray computed tomography using a superiorization approach

    SciTech Connect (OSTI)

    Schrapp, Michael J. [Siemens AG, CT Munich, Germany and Physics Department E21, Technical University of Munich, Munich (Germany)] [Siemens AG, CT Munich, Germany and Physics Department E21, Technical University of Munich, Munich (Germany); Herman, Gabor T. [Department of Computer Science, The Graduate Center, City University of New York, New York, New York 10016 (United States)] [Department of Computer Science, The Graduate Center, City University of New York, New York, New York 10016 (United States)

    2014-05-15T23:59:59.000Z

    X-ray computed tomography (CT) is an important and widespread inspection technique in industrial non-destructive testing. However, large-sized and heavily absorbing objects cause artifacts due to either the lack of penetration of the specimen in specific directions or by having data from only a limited angular range of views. In such cases, valuable information about the specimen is not revealed by the CT measurements alone. Further imaging modalities, such as optical scanning and ultrasonic testing, are able to provide data (such as an edge map) that are complementary to the CT acquisition. In this paper, a superiorization approach (a newly developed method for constrained optimization) is used to incorporate the complementary data into the CT reconstruction; this allows precise localization of edges that are not resolvable from the CT data by itself. Superiorization, as presented in this paper, exploits the fact that the simultaneous algebraic reconstruction technique (SART), often used for CT reconstruction, is resilient to perturbations; i.e., it can be modified to produce an output that is as consistent with the CT measurements as the output of unmodified SART, but is more consistent with the complementary data. The application of this superiorized SART method to measured data of a turbine blade demonstrates a clear improvement in the quality of the reconstructed image.

  19. Fast reconstruction algorithms for the thermoacoustic tomography in certain domains with cylindrical or spherical symmetries

    E-Print Network [OSTI]

    Kunyansky, Leonid

    2011-01-01T23:59:59.000Z

    We propose three fast algorithms for solving the inverse problem of the thermoacoustic tomography corresponding to certain acquisition geometries. Two of these methods are designed to process the measurements done with point-like detectors placed on a circle (in 2D) or a sphere (in 3D) surrounding the object of interest. The third inversion algorithm works with the data measured by the integrating line detectors arranged in a cylindrical assembly rotating around the object. The number of operations required by these techniques is equal to O(n^3 log n) and O(n^3 log^2 n) for the 3D techniques (assuming the reconstruction grid with n^3 nodes) and to O(n^2 log n) for the 2D problem with n-by-n discretizetion grid. Numerical simulations show that our methods are at least two orders of magnitude faster than the existing algorithms, without any sacrifice in accuracy or stability. The results of reconstructions from real measurements done by the integrating line detectors are also presented, to demonstrate the pract...

  20. An overview of the CUJET model: Jet Flavor Tomography applied at RHIC and LHC

    E-Print Network [OSTI]

    Alessandro Buzzatti; Miklos Gyulassy

    2012-10-01T23:59:59.000Z

    Jet Flavor Tomography is a powerful tool used to probe the properties of Quark Gluon Plasma formed in heavy ion collisions at RHIC and LHC. A new Monte Carlo model of jet quenching developed at Columbia University, CUJET, was applied to predict the jet flavor and centrality dependence of the nuclear modification factor $R_{AA}$. The predictions for fragments $f=\\pi,D,B,e$, derived from quenched jet flavors $a=g,u,c,b$ in central and peripheral collisions at RHIC and LHC, exhibit novel features such as a level crossing pattern in $R_{AA\\rightarrow a\\rightarrow f}$ over a broad transverse momentum range which can test jet-medium dynamics in quark gluon plasmas and help discriminate between current energy loss models. Furthermore, the inclusion of running coupling effects seems to change the jet energy dependence of the jet energy loss to a non trivial constant behavior, with a visible impact on the predictions for $R_{AA}$.

  1. MAPPING EARTH ANALOGS FROM PHOTOMETRIC VARIABILITY: SPIN-ORBIT TOMOGRAPHY FOR PLANETS IN INCLINED ORBITS

    SciTech Connect (OSTI)

    Fujii, Yuka [Department of Physics, University of Tokyo, Tokyo 113-0033 (Japan); Kawahara, Hajime, E-mail: yuka.fujii@utap.phys.s.u-tokyo.ac.jp [Department of Physics, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397 (Japan)

    2012-08-20T23:59:59.000Z

    Aiming at obtaining detailed information on the surface environment of Earth analogs, Kawahara and Fujii proposed an inversion technique of annual scattered light curves named spin-orbit tomography (SOT), which enables us to sketch a two-dimensional albedo map from annual variation of the disk-integrated scattered light, and demonstrated the method with a planet in a face-on orbit. We extend it to be applicable to general geometric configurations, including low-obliquity planets like the Earth in inclined orbits. We simulate light curves of the Earth in an inclined orbit in three photometric bands (0.4-0.5 {mu}m, 0.6-0.7 {mu}m, and 0.8-0.9 {mu}m) and show that the distribution of clouds, snow, and continents is retrieved with the aid of the SOT. We also demonstrate the SOT by applying it to an upright Earth, a tidally locked Earth, and Earth analogs with ancient continental configurations. The inversion is model independent in the sense that we do not assume specific albedo models when mapping the surface, and hence applicable in principle to any kind of inhomogeneity. This method can potentially serve as a unique tool to investigate the exohabitats/exoclimes of Earth analogs.

  2. Performance of Hull-Detection Algorithms For Proton Computed Tomography Reconstruction

    E-Print Network [OSTI]

    Schultze, Blake; Censor, Yair; Schulte, Reinhard; Schubert, Keith Evan

    2014-01-01T23:59:59.000Z

    Proton computed tomography (pCT) is a novel imaging modality developed for patients receiving proton radiation therapy. The purpose of this work was to investigate hull-detection algorithms used for preconditioning of the large and sparse linear system of equations that needs to be solved for pCT image reconstruction. The hull-detection algorithms investigated here included silhouette/space carving (SC), modified silhouette/space carving (MSC), and space modeling (SM). Each was compared to the cone-beam version of filtered backprojection (FBP) used for hull-detection. Data for testing these algorithms included simulated data sets of a digital head phantom and an experimental data set of a pediatric head phantom obtained with a pCT scanner prototype at Loma Linda University Medical Center. SC was the fastest algorithm, exceeding the speed of FBP by more than 100 times. FBP was most sensitive to the presence of noise. Ongoing work will focus on optimizing threshold parameters in order to define a fast and effic...

  3. X-Ray Energy Responses of Silicon Tomography Detectors Irradiated with Fusion Produced Neutrons

    SciTech Connect (OSTI)

    Kohagura, J. [Plasma Research Centre, University of Tsukuba (Japan); Cho, T. [Plasma Research Centre, University of Tsukuba (Japan); Hirata, M. [Plasma Research Centre, University of Tsukuba (Japan); Numakura, T. [Plasma Research Centre, University of Tsukuba (Japan); Yokoyama, N. [Plasma Research Centre, University of Tsukuba (Japan); Fukai, T. [Plasma Research Centre, University of Tsukuba (Japan); Tomii, Y. [Plasma Research Centre, University of Tsukuba (Japan); Tokioka, S. [Plasma Research Centre, University of Tsukuba (Japan); Miyake, Y. [Plasma Research Centre, University of Tsukuba (Japan); Kiminami, S. [Plasma Research Centre, University of Tsukuba (Japan); Shimizu, K. [Plasma Research Centre, University of Tsukuba (Japan); Miyoshi, S. [Plasma Research Centre, University of Tsukuba (Japan); Hirano, K. [High Energy Accelerator Research Organization (Japan); Yoshida, M. [Japan Atomic Energy Research Institute (Japan); Yamauchi, M. [Japan Atomic Energy Research Institute (Japan); Kondoh, T. [Japan Atomic Energy Research Institute (Japan); Nishitani, T. [Japan Atomic Energy Research Institute (Japan)

    2005-01-15T23:59:59.000Z

    In order to clarify the effects of fusion-produced neutron irradiation on silicon semiconductor x-ray detectors, the x-ray energy responses of both n- and p-type silicon tomography detectors used in the Joint European Torus (JET) tokamak (n-type) and the GAMMA 10 tandem mirror (p-type) are studied using synchrotron radiation at the Photon Factory of the National Laboratory for High Energy Accelerator Research Organization (KEK). The fusion neutronics source (FNS) of Japan Atomic Energy Research Institute (JAERI) is employed as well-calibrated D-T neutron source with fluences from 10{sup 13} to 10{sup 15} neutrons/cm{sup 2} onto these semiconductor detectors. Different fluence dependence is found between these two types of detectors; that is, (i) for the n-type detector, the recovery of the degraded response is found after the neutron exposure beyond around 10{sup 13} neutrons/cm{sup 2} onto the detector. A further finding is followed as a 're-degradation' by a neutron irradiation level over about 10{sup 14} neutrons/cm{sup 2}. On the other hand, (ii) the energy response of the p-type detector shows only a gradual decrease with increasing neutron fluences. These properties are interpreted by our proposed theory on semiconductor x-ray responses in terms of the effects of neutrons on the effective doping concentration and the diffusion length of a semiconductor detector.

  4. Reconstruction for proton computed tomography by tracing proton trajectories: A Monte Carlo study

    SciTech Connect (OSTI)

    Li Tianfang; Liang Zhengrong; Singanallur, Jayalakshmi V.; Satogata, Todd J.; Williams, David C.; Schulte, Reinhard W. [Departments of Radiology, Computer Science, and Physics and Astronomy, State University of New York at Stony Brook, Stony Brook, New York 11794 (United States); Department of Physics, Brookhaven National Laboratory, Upton, New York 11973 (United States); Santa Cruz Institute for Particle Physics, University of California at Santa Cruz, Santa Cruz, California 95064 (United States); Department of Radiation Medicine, Loma Linda University Medical Center, Loma Linda, California 92354 (United States)

    2006-03-15T23:59:59.000Z

    Proton computed tomography (pCT) has been explored in the past decades because of its unique imaging characteristics, low radiation dose, and its possible use for treatment planning and on-line target localization in proton therapy. However, reconstruction of pCT images is challenging because the proton path within the object to be imaged is statistically affected by multiple Coulomb scattering. In this paper, we employ GEANT4-based Monte Carlo simulations of the two-dimensional pCT reconstruction of an elliptical phantom to investigate the possible use of the algebraic reconstruction technique (ART) with three different path-estimation methods for pCT reconstruction. The first method assumes a straight-line path (SLP) connecting the proton entry and exit positions, the second method adapts the most-likely path (MLP) theoretically determined for a uniform medium, and the third method employs a cubic spline path (CSP). The ART reconstructions showed progressive improvement of spatial resolution when going from the SLP [2 line pairs (lp) cm{sup -1}] to the curved CSP and MLP path estimates (5 lp cm{sup -1}). The MLP-based ART algorithm had the fastest convergence and smallest residual error of all three estimates. This work demonstrates the advantage of tracking curved proton paths in conjunction with the ART algorithm and curved path estimates.

  5. Atom probe tomography studies of Al?O? gate dielectrics on GaN

    SciTech Connect (OSTI)

    Mazumder, Baishakhi, E-mail: bmazumder@engineering.ucsb.edu; Wu, Feng; Speck, James S. [Materials Department, University of California, Santa Barbara, California 93106 (United States); Liu, Xiang; Yeluri, Ramya; Mishra, Umesh K. [Electrical and Computer Engineering Department, University of California, Santa Barbara, California 93106 (United States)

    2014-10-07T23:59:59.000Z

    Atom probe tomography was used to achieve three-dimensional characterization of in situ Al?O?/GaN structures grown by metal organic chemical vapor deposition (MOCVD). Al?O? dielectrics grown at three different temperatures of 700, 900, and 1000 °C were analyzed and compared. A low temperature GaN cap layer grown atop Al?O? enabled a high success rate in the atom probe experiments. The Al?O?/GaN interfaces were found to be intermixed with Ga, N, and O over the distance of a few nm. Impurity measurements data showed that the 1000 °C sample contains higher amounts of C (4 × 10ą?/cmł) and lower amounts of H (7 × 10ą?/cmł), whereas the 700 °C sample exhibits lower C impurities (<10ą?/cmł) and higher H incorporation (2.2 × 10˛?/cmł). On comparing with Al?O? grown by atomic layer deposition (ALD), it was found that the MOCVD Al?O?/GaN interface is comparatively abrupt. Scanning transmission electron microscopy data showed that the 900 °C and 1000 °C MOCVD films exhibit polycrystalline nature, while the ALD films were found to be amorphous.

  6. Bayesian soft X-ray tomography using non-stationary Gaussian Processes

    SciTech Connect (OSTI)

    Li, Dong; Svensson, J.; Thomsen, H.; Werner, A.; Wolf, R. [Max Planck Institute for Plasma Physics, Teilinstitut, D-17491 Greifswald (Germany)] [Max Planck Institute for Plasma Physics, Teilinstitut, D-17491 Greifswald (Germany); Medina, F. [Asociación EURATOM-CIEMAT, Madrid (Spain)] [Asociación EURATOM-CIEMAT, Madrid (Spain)

    2013-08-15T23:59:59.000Z

    In this study, a Bayesian based non-stationary Gaussian Process (GP) method for the inference of soft X-ray emissivity distribution along with its associated uncertainties has been developed. For the investigation of equilibrium condition and fast magnetohydrodynamic behaviors in nuclear fusion plasmas, it is of importance to infer, especially in the plasma center, spatially resolved soft X-ray profiles from a limited number of noisy line integral measurements. For this ill-posed inversion problem, Bayesian probability theory can provide a posterior probability distribution over all possible solutions under given model assumptions. Specifically, the use of a non-stationary GP to model the emission allows the model to adapt to the varying length scales of the underlying diffusion process. In contrast to other conventional methods, the prior regularization is realized in a probability form which enhances the capability of uncertainty analysis, in consequence, scientists who concern the reliability of their results will benefit from it. Under the assumption of normally distributed noise, the posterior distribution evaluated at a discrete number of points becomes a multivariate normal distribution whose mean and covariance are analytically available, making inversions and calculation of uncertainty fast. Additionally, the hyper-parameters embedded in the model assumption can be optimized through a Bayesian Occam's Razor formalism and thereby automatically adjust the model complexity. This method is shown to produce convincing reconstructions and good agreements with independently calculated results from the Maximum Entropy and Equilibrium-Based Iterative Tomography Algorithm methods.

  7. Cone beam x-ray luminescence computed tomography: A feasibility study

    SciTech Connect (OSTI)

    Chen Dongmei; Zhu Shouping; Yi Huangjian; Zhang Xianghan; Chen Duofang; Liang Jimin [School of Life Sciences and Technology, Xidian University, Xi'an 710071 (China); Tian Jie [School of Life Sciences and Technology, Xidian University, Xi'an 710071 (China); Medical Image Processing Group, Institute of Automation, Chinese Academy of Sciences, Beijing 100190 (China)

    2013-03-15T23:59:59.000Z

    Purpose: The appearance of x-ray luminescence computed tomography (XLCT) opens new possibilities to perform molecular imaging by x ray. In the previous XLCT system, the sample was irradiated by a sequence of narrow x-ray beams and the x-ray luminescence was measured by a highly sensitive charge coupled device (CCD) camera. This resulted in a relatively long sampling time and relatively low utilization of the x-ray beam. In this paper, a novel cone beam x-ray luminescence computed tomography strategy is proposed, which can fully utilize the x-ray dose and shorten the scanning time. The imaging model and reconstruction method are described. The validity of the imaging strategy has been studied in this paper. Methods: In the cone beam XLCT system, the cone beam x ray was adopted to illuminate the sample and a highly sensitive CCD camera was utilized to acquire luminescent photons emitted from the sample. Photons scattering in biological tissues makes it an ill-posed problem to reconstruct the 3D distribution of the x-ray luminescent sample in the cone beam XLCT. In order to overcome this issue, the authors used the diffusion approximation model to describe the photon propagation in tissues, and employed the sparse regularization method for reconstruction. An incomplete variables truncated conjugate gradient method and permissible region strategy were used for reconstruction. Meanwhile, traditional x-ray CT imaging could also be performed in this system. The x-ray attenuation effect has been considered in their imaging model, which is helpful in improving the reconstruction accuracy. Results: First, simulation experiments with cylinder phantoms were carried out to illustrate the validity of the proposed compensated method. The experimental results showed that the location error of the compensated algorithm was smaller than that of the uncompensated method. The permissible region strategy was applied and reduced the reconstruction error to less than 2 mm. The robustness and stability were then evaluated from different view numbers, different regularization parameters, different measurement noise levels, and optical parameters mismatch. The reconstruction results showed that the settings had a small effect on the reconstruction. The nonhomogeneous phantom simulation was also carried out to simulate a more complex experimental situation and evaluated their proposed method. Second, the physical cylinder phantom experiments further showed similar results in their prototype XLCT system. With the discussion of the above experiments, it was shown that the proposed method is feasible to the general case and actual experiments. Conclusions: Utilizing numerical simulation and physical experiments, the authors demonstrated the validity of the new cone beam XLCT method. Furthermore, compared with the previous narrow beam XLCT, the cone beam XLCT could more fully utilize the x-ray dose and the scanning time would be shortened greatly. The study of both simulation experiments and physical phantom experiments indicated that the proposed method was feasible to the general case and actual experiments.

  8. 2-D Coda and Direct Wave Attenuation Tomography in Northern Italy

    SciTech Connect (OSTI)

    Morasca, P; Mayeda, K; Gok, R; Phillips, W S; Malagnini, L

    2007-10-17T23:59:59.000Z

    A 1-D coda method was proposed by Mayeda et al. (2003) in order to obtain stable seismic source moment-rate spectra using narrowband coda envelope measurements. That study took advantage of the averaging nature of coda waves to derive stable amplitude measurements taking into account all propagation, site, and Sto-coda transfer function effects. Recently this methodology was applied to micro earthquake data sets from three sub-regions of northern Italy (i.e., western Alps, northern Apennines and eastern Alps). Since the study regions were small, ranging between local-to-near-regional distances, the simple 1-D path assumptions used in the coda method worked very well. The lateral complexity of this region would suggest, however, that a 2-D path correction might provide even better results if the datasets were combined, especially when paths traverse larger distances and complicated regions. The structural heterogeneity of northern Italy makes the region ideal to test the extent to which coda variance can be reduced further by using a 2-D Q tomography technique. The approach we use has been developed by Phillips et al. (2005) and is an extension of previous amplitude ratio techniques to remove source effects from the inversion. The method requires some assumptions such as isotropic source radiation which is generally true for coda waves. Our results are compared against direct Swave inversions for 1/Q and results from both share very similar attenuation features that coincide with known geologic structures. We compare our results with those derived from direct waves as well as some recent results from northern California obtained by Mayeda et al. (2005) which tested the same tomographic methodology applied in this study to invert for 1/Q. We find that 2-D coda path corrections for this region significantly improve upon the 1-D corrections, in contrast to California where only a marginal improvement was observed. We attribute this difference to stronger lateral variations in Q for northern Italy relative to California.

  9. Positron Emission Tomography (PET) Evaluation After Initial Chemotherapy and Radiation Therapy Predicts Local Control in Rhabdomyosarcoma

    SciTech Connect (OSTI)

    Dharmarajan, Kavita V., E-mail: dharmark@mskcc.org [Departments of Radiation Oncology, Pediatric Oncology, and Nuclear Medicine, Memorial Sloan-Kettering, New York, New York (United States); Wexler, Leonard H.; Gavane, Somali; Fox, Josef J.; Schoder, Heiko; Tom, Ashlyn K.; Price, Alison N.; Meyers, Paul A.; Wolden, Suzanne L. [Departments of Radiation Oncology, Pediatric Oncology, and Nuclear Medicine, Memorial Sloan-Kettering, New York, New York (United States)] [Departments of Radiation Oncology, Pediatric Oncology, and Nuclear Medicine, Memorial Sloan-Kettering, New York, New York (United States)

    2012-11-15T23:59:59.000Z

    Purpose: 18-fluorodeoxyglucose positron emission tomography (PET) is already an integral part of staging in rhabdomyosarcoma. We investigated whether primary-site treatment response characterized by serial PET imaging at specific time points can be correlated with local control. Patients and Methods: We retrospectively examined 94 patients with rhabdomyosarcoma who received initial chemotherapy 15 weeks (median) before radiotherapy and underwent baseline, preradiation, and postradiation PET. Baseline PET standardized uptake values (SUVmax) and the presence or absence of abnormal uptake (termed PET-positive or PET-negative) both before and after radiation were examined for the primary site. Local relapse-free survival (LRFS) was calculated according to baseline SUVmax, PET-positive status, and PET-negative status by the Kaplan-Meier method, and comparisons were tested with the log-rank test. Results: The median patient age was 11 years. With 3-year median follow-up, LRFS was improved among postradiation PET-negative vs PET-positive patients: 94% vs 75%, P=.02. By contrast, on baseline PET, LRFS was not significantly different for primary-site SUVmax {<=}7 vs >7 (median), although the findings suggested a trend toward improved LRFS: 96% for SUVmax {<=}7 vs 79% for SUVmax >7, P=.08. Preradiation PET also suggested a statistically insignificant trend toward improved LRFS for PET-negative (97%) vs PET-positive (81%) patients (P=.06). Conclusion: Negative postradiation PET predicted improved LRFS. Notably, 77% of patients with persistent postradiation uptake did not experience local failure, suggesting that these patients could be closely followed up rather than immediately referred for intervention. Negative baseline and preradiation PET findings suggested statistically insignificant trends toward improved LRFS. Additional study may further understanding of relationships between PET findings at these time points and outcome in rhabdomyosarcoma.

  10. Comparison of electrical capacitance tomography and gamma densitometer measurement in viscous oil-gas flows

    SciTech Connect (OSTI)

    Archibong Eso, A.; Zhao, Yabin; Yeung, Hoi [Department of Offshore Process and Energy Systems Engineering, Cranfield University, Cranfield (United Kingdom)

    2014-04-11T23:59:59.000Z

    Multiphase flow is a common occurrence in industries such as nuclear, process, oil and gas, food and chemical. A prior knowledge of its features and characteristics is essential in the design, control and management of such processes due to its complex nature. Electrical Capacitance Tomography (ECT) and Gamma Densitometer (Gamma) are two promising approaches for multiphase visualization and characterization in process industries. In two phase oil and gas flow, ECT and Gamma are used in multiphase flow monitoring techniques due to their inherent simplicity, robustness, and an ability to withstand wide range of operational temperatures and pressures. High viscous oil (viscosity > 100 cP) is of interest because of its huge reserves, technological advances in its production and unlike conventional oil (oil viscosity < 100 cP) and gas flows where ECT and Gamma have been previously used, high viscous oil and gas flows comes with certain associated concerns which include; increased entrainment of gas bubbles dispersed in oil, shorter and more frequent slugs as well as oil film coatings on the walls of flowing conduits. This study aims to determine the suitability of both devices in the visualization and characterization of high-viscous oil and gas flow. Static tests are performed with both devices and liquid holdup measurements are obtained. Dynamic experiments were also conducted in a 1 and 3 inch facility at Cranfield University with a range of nominal viscosities (1000, 3000 and 7500 cP). Plug, slug and wavy annular flow patterns were identified by means of Probability Mass Function and time series analysis of the data acquired from Gamma and ECT devices with high speed camera used to validate the results. Measured Liquid holdups for both devices were also compared.

  11. Respiratory triggered 4D cone-beam computed tomography: A novel method to reduce imaging dose

    SciTech Connect (OSTI)

    Cooper, Benjamin J. [Radiation Physics Laboratory, Sydney Medical School, University of Sydney, NSW 2006, Australia and Department of Medical Physics and Radiation Engineering, Canberra Hospital, Canberra, ACT 2605 (Australia); O'Brien, Ricky T.; Keall, Paul J. [Radiation Physics Laboratory, Sydney Medical School, University of Sydney, NSW 2006 (Australia); Balik, Salim; Hugo, Geoffrey D. [Radiation Oncology, Virginia Commonwealth University, 401 College Street, P.O.Box 980058, Richmond, Virginia 23298-0058 (United States)

    2013-04-15T23:59:59.000Z

    Purpose: A novel method called respiratory triggered 4D cone-beam computed tomography (RT 4D CBCT) is described whereby imaging dose can be reduced without degrading image quality. RT 4D CBCT utilizes a respiratory signal to trigger projections such that only a single projection is assigned to a given respiratory bin for each breathing cycle. In contrast, commercial 4D CBCT does not actively use the respiratory signal to minimize image dose. Methods: To compare RT 4D CBCT with conventional 4D CBCT, 3600 CBCT projections of a thorax phantom were gathered and reconstructed to generate a ground truth CBCT dataset. Simulation pairs of conventional 4D CBCT acquisitions and RT 4D CBCT acquisitions were developed assuming a sinusoidal respiratory signal which governs the selection of projections from the pool of 3600 original projections. The RT 4D CBCT acquisition triggers a single projection when the respiratory signal enters a desired acquisition bin; the conventional acquisition does not use a respiratory trigger and projections are acquired at a constant frequency. Acquisition parameters studied were breathing period, acquisition time, and imager frequency. The performance of RT 4D CBCT using phase based and displacement based sorting was also studied. Image quality was quantified by calculating difference images of the test dataset from the ground truth dataset. Imaging dose was calculated by counting projections. Results: Using phase based sorting RT 4D CBCT results in 47% less imaging dose on average compared to conventional 4D CBCT. Image quality differences were less than 4% at worst. Using displacement based sorting RT 4D CBCT results in 57% less imaging dose on average, than conventional 4D CBCT methods; however, image quality was 26% worse with RT 4D CBCT. Conclusions: Simulation studies have shown that RT 4D CBCT reduces imaging dose while maintaining comparable image quality for phase based 4D CBCT; image quality is degraded for displacement based RT 4D CBCT in its current implementation.

  12. Efficacy of Lower-Body Shielding in Computed Tomography Fluoroscopy-Guided Interventions

    SciTech Connect (OSTI)

    Mahnken, Andreas H., E-mail: mahnken@rad.rwth-aachen.de [RWTH Aachen, Department of Diagnostic and Interventional Radiology (Germany); Sedlmair, Martin [Siemens, Healthcare Sector (Germany); Ritter, Christine [University of Copenhagen, Niels Bohr Institute (Denmark); Banckwitz, Rosemarie; Flohr, Thomas [Siemens, Healthcare Sector (Germany)

    2012-12-15T23:59:59.000Z

    Purpose: Computed tomography (CT) fluoroscopy-guided interventions pose relevant radiation exposure to the interventionalist. The goal of this study was to analyze the efficacy of lower-body shielding as a simple structural method for decreasing radiation dose to the interventionalist without limiting access to the patient. Material and Methods: All examinations were performed with a 128-slice dual source CT scanner (12 Multiplication-Sign 1.2-mm collimation; 120 kV; and 20, 40, 60, and 80 mAs) and an Alderson-Rando phantom. Scatter radiation was measured with an ionization chamber and a digital dosimeter at standardized positions and heights with and without a lower-body lead shield (0.5-mm lead equivalent; Kenex, Harlow, UK). Dose decreases were computed for the different points of measurement. Results: On average, lower-body shielding decreased scatter radiation by 38.2% within a 150-cm radius around the shielding. This decrease is most significant close to the gantry opening and at low heights of 50 and 100 cm above the floor with a maximum decrease of scatter radiation of 95.9% close to the scanner's isocentre. With increasing distance to the gantry opening, the effect decreased. There is almost no dose decrease effect at {>=}150 above the floor. Scatter radiation and its decrease were linearly correlated with the tube current-time product (r{sup 2} = 0.99), whereas percent scatter radiation decrease was independent of the tube current-time product. Conclusion: Lower-body shielding is an effective way to decrease radiation exposure to the interventionalist and should routinely be used in CT fluoroscopy-guided interventions.

  13. Design of Mega-Voltage X-ray Digital Radiography and Computed Tomography Performance Phantoms

    SciTech Connect (OSTI)

    Aufderheide, M B; Martz, H E; Curtin, M

    2009-06-22T23:59:59.000Z

    A number of fundamental scientific questions have arisen concerning the operation of high-energy DR and CT systems. Some of these questions include: (1) How deeply can such systems penetrate thickly shielded objects? (2) How well can such systems distinguish between dense and relatively high Z materials such as lead, tungsten and depleted uranium and lower Z materials such as steel, copper and tin? (3) How well will such systems operate for a uranium material which is an intermediate case between low density yellowcake and high density depleted uranium metal? These questions have led us to develop a set of phantoms to help answer these questions, but do not have any direct bearing on any smuggling concern. These new phantoms are designed to allow a systemic exploration of these questions by gradually varying their compositions and thicknesses. These phantoms are also good probes of the blurring behavior of radiography and tomography systems. These phantoms are composed of steel ({rho} assumed to be 7.8 g/cc), lead ({rho} assumed to be 11.4 g/cc), tungsten ({rho} assumed to be 19.25 g/cc), uranium oxide (UO{sub 3}) ({rho} assumed to be 4.6 g/cc), and depleted uranium (DU) ({rho} assumed to be 18.9 g/cc). There are five designed phantoms described in this report: (1) Cylindrical shells of Tungsten and Steel; (2) Depleted Uranium Inside Tungsten Hemi-cube Shells; (3) Nested Spherical Shells; (4) UO{sub 3} Cylinder; and (5) Shielded DU Sphere.

  14. Lung Tumors Treated With Percutaneous Radiofrequency Ablation: Computed Tomography Imaging Follow-Up

    SciTech Connect (OSTI)

    Palussiere, Jean, E-mail: palussiere@bergonie.org; Marcet, Benjamin; Descat, Edouard [Institut Bergonie, Regional Cancer Center, Department of Interventional Radiology (France); Deschamps, Frederic; Rao, Pramod [Institut Gustave Roussy, Department of Interventional Radiology (France); Ravaud, Alain [Hopital Saint-Andre, Department of Medical Oncology (France); Brouste, Veronique [Institut Bergonie, Department of Biostatistics (France); Baere, Thierry de [Institut Gustave Roussy, Department of Interventional Radiology (France)

    2011-10-15T23:59:59.000Z

    Purpose: To describe the morphologic evolution of lung tumors treated with radiofrequency ablation (RFA) by way of computed tomography (CT) images and to investigate patterns of incomplete RFA at the site of ablation. Materials and Methods: One hundred eighty-nine patients with 350 lung tumors treated with RFA underwent CT imaging at 2, 4, 6, and 12 months. CT findings were interpreted separately by two reviewers with consensus. Five different radiologic patterns were predefined: fibrosis, cavitation, nodule, atelectasis, and disappearance. The appearance of the treated area was evaluated at each follow-up CT using the predefined patterns. Results: At 1 year after treatment, the most common evolutions were fibrosis (50.5%) or nodules (44.8%). Differences were noted depending on the initial size of the tumor, with fibrosis occurring more frequently for tumors <2 cm (58.6% vs. 22.9%, P = 1 Multiplication-Sign 10{sup -5}). Cavitation and atelectasis were less frequent patterns (2.4% and 1.4%, respectively, at 1 year). Tumor location (intraparenchymatous, with pleural contact <50% or >50%) was not significantly correlated with follow-up image pattern. Local tumor progressions were observed with each type of evolution. At 1 year, 12 local recurrences were noted: 2 cavitations, which represented 40% of the cavitations noted at 1 year; 2 fibroses (1.9%); 7 nodules (7.4%); and 1 atelectasis (33.3%). Conclusion: After RFA of lung tumors, follow-up CT scans show that the shape of the treatment zone can evolve in five different patterns. None of these patterns, however, can confirm the absence of further local tumor progression at subsequent follow-up.

  15. Demonstration of Emitted-Neutron Computed Tomography to Count Fuel Pins

    SciTech Connect (OSTI)

    Hausladen, Paul [ORNL] [ORNL; Blackston, Matthew A [ORNL] [ORNL; Brubaker, E. [Sandia National Laboratories (SNL)] [Sandia National Laboratories (SNL); Chichester, David [Idaho National Laboratory (INL)] [Idaho National Laboratory (INL); Marleau, P. [Sandia National Laboratories (SNL)] [Sandia National Laboratories (SNL); Newby, Robert Jason [ORNL] [ORNL

    2012-01-01T23:59:59.000Z

    In this paper, we report demonstration of emitted-neutron computed tomography using fast fission neutrons to infer the geometry of sources of special nuclear material (SNM) such as fuel pins. In a proof-of-concept measurement at the Idaho National Laboratory s (INL s) Zero Power Physics Reactor (ZPPR) facility, an array of unirradiated Pu MOX fuel rodlets in a soup can were imaged, and a bias defect consisting of a single rodlet containing Pu replaced by one containing depleted uranium (DU) was detected. The imaging system employed in the demonstration is based on a newly constructed array of pixelated neutron detectors that are suitable for arrangement in a close-packed imaging array and whose active volume consists of liquid scintillator EJ-309 which allows neutron-gamma discrimination via pulse shape to enable pure fast-neutron imaging. The imaging array was used along with a radial collimator aperture in order to perform high quality fast-neutron imaging where tomographic reconstruction of slices through an object resolve neutron sources similar in dimension to a fuel pellet, or about 1 cm. Measurements were performed at Oak Ridge National Laboratory (ORNL) with neutron sources in addition to those performed at the INL s ZPPR facility with Pu MOX fuel rodlets. An analogous capability to detect single-pin defects in spent fuel assemblies would be desirable, such as for safeguards verification measurements of spent fuel assemblies just prior to transferring them from the spent fuel cooling pool to long term dry cask storage. This paper describes the design and construction of the present imager, characterization measurements with neutron sources at ORNL, measurements with SNM at INL s ZPPR facility, and feasibility of building an analogous imager for spent fuel measurements.

  16. Demonstration of Emitted-Neutron Computed Tomography to Count Fuel Pins

    SciTech Connect (OSTI)

    P. A. Hausladen; M. A. Blackston; E. Brubaker; D. L. Chichester; P. Marleau; R. J. Newby

    2012-07-01T23:59:59.000Z

    In this paper, we report demonstration of emitted-neutron computed tomography using fast fission neutrons to infer the geometry of sources of special nuclear material (SNM) such as fuel pins. In a proof-of-concept measurement at the Idaho National Laboratory’s (INL’s) Zero Power Physics Reactor (ZPPR) facility, an array of unirradiated Pu MOX fuel rodlets in a soup can were imaged, and a bias defect consisting of a single rodlet containing Pu replaced by one containing depleted uranium (DU) was detected. The imaging system employed in the demonstration is based on a newly constructed array of pixelated neutron detectors that are suitable for arrangement in a close-packed imaging array and whose active volume consists of liquid scintillator EJ-309 which allows neutron-gamma discrimination via pulse shape to enable pure fast-neutron imaging. The imaging array was used along with a radial collimator aperture in order to perform high quality fast-neutron imaging where tomographic reconstruction of slices through an object resolve neutron sources similar in dimension to a fuel pellet, or about 1 cm. Measurements were performed at Oak Ridge National Laboratory (ORNL) with neutron sources in addition to those performed at the INL’s ZPPR facility with Pu MOX fuel rodlets. An analogous capability to detect single-pin defects in spent fuel assemblies would be desirable, such as for safeguards verification measurements of spent fuel assemblies just prior to transferring them from the spent fuel cooling pool to long term dry cask storage. This paper describes the design and construction of the present imager, characterization measurements with neutron sources at ORNL, measurements with SNM at INL’s ZPPR facility, and feasibility of building an analogous imager for spent fuel measurements.

  17. PILOT-SCALE FIELD VALIDATION OF THE LONG ELECTRODE ELECTRICAL RESISTIVITY TOMOGRAPHY METHOD

    SciTech Connect (OSTI)

    GLASER DR; RUCKER DF; CROOK N; LOKE MH

    2011-07-14T23:59:59.000Z

    Field validation for the long electrode electrical resistivity tomography (LE-ERT) method was attempted in order to demonstrate the performance of the technique in imaging a simple buried target. The experiment was an approximately 1/17 scale mock-up of a region encompassing a buried nuclear waste tank on the Hanford site. The target of focus was constructed by manually forming a simulated plume within the vadose zone using a tank waste simulant. The LE-ERT results were compared to ERT using conventional point electrodes on the surface and buried within the survey domain. Using a pole-pole array, both point and long electrode imaging techniques identified the lateral extents of the pre-formed plume with reasonable fidelity, but the LE-ERT was handicapped in reconstructing the vertical boundaries. The pole-dipole and dipole-dipole arrays were also tested with the LE-ERT method and were shown to have the least favorable target properties, including the position of the reconstructed plume relative to the known plume and the intensity of false positive targets. The poor performance of the pole-dipole and dipole-dipole arrays was attributed to an inexhaustive and non-optimal coverage of data at key electrodes, as well as an increased noise for electrode combinations with high geometric factors. However, when comparing the model resolution matrix among the different acquisition strategies, the pole-dipole and dipole-dipole arrays using long electrodes were shown to have significantly higher average and maximum values than any pole-pole array. The model resolution describes how well the inversion model resolves the subsurface. Given the model resolution performance of the pole-dipole and dipole-dipole arrays, it may be worth investing in tools to understand the optimum subset of randomly distributed electrode pairs to produce maximum performance from the inversion model.

  18. Characterization of conditional state-engineering quantum processes by coherent state quantum process tomography

    E-Print Network [OSTI]

    Merlin Cooper; Eirion Slade; Michal Karpinski; Brian J. Smith

    2014-10-25T23:59:59.000Z

    Conditional quantum optical processes enable a wide range of technologies from generation of highly non-classical states to implementation of quantum logic operations. The process fidelity that can be achieved in a realistic implementation depends on a number of system parameters. Here we experimentally examine Fock-state filtration, a canonical example of a broad class of conditional quantum operations acting on a single optical field mode. This operation is based upon interference of the mode to be manipulated with an auxiliary single-photon state at a beam splitter, resulting in the entanglement of the two output modes. A conditional projective measurement onto a single photon at one output mode heralds the success of the process. This operation, which implements a measurement-induced nonlinearity, is capable of suppressing particular photon-number probability amplitudes of an arbitrary quantum state. We employ coherent-state process tomography to determine the precise operation realized in our experiment. To identify the key sources of experimental imperfection, we develop a model of the process and identify three main contributions that significantly hamper its efficacy. The reconstructed tensor is compared with a model of the process taking into account sources of experimental imperfection with fidelity better than 0.95. This enables us to identify three key challenges to overcome in realizing a filter with high fidelity - namely the single-photon nature of the auxiliary state, high-mode overlap, and the need for number resolving detection when heralding. The results show that the filter does indeed exhibit a nonlinear response as a function of input photon number and preserves the phase relation between Fock layers of the output state, providing promise for future applications.

  19. Enhancement of the resolution of full-field optical coherence tomography by using a colour image sensor

    SciTech Connect (OSTI)

    Kalyanov, A L; Lychagov, V V; Smirnov, I V; Ryabukho, V P [N.G. Chernyshevsky Saratov State University, Saratov (Russian Federation)

    2013-08-31T23:59:59.000Z

    The influence of white balance in a colour image detector on the resolution of a full-field optical coherence tomograph (FFOCT) is studied. The change in the interference pulse width depending on the white balance tuning is estimated in the cases of a thermal radiation source (incandescent lamp) and a white light emitting diode. It is shown that by tuning white balance of the detector in a certain range, the FFOCT resolution can be increased by 20 % as compared to the resolution, attained with the use of a monochrome detector. (optical coherence tomography)

  20. Evaluation of Vascular Supply with Angio-Computed Tomography During Intra-Arterial Chemotherapy for Brain Tumors

    SciTech Connect (OSTI)

    Hirai, Toshinori, E-mail: toshinor@beige.ocn.ne.jp; Korogi, Yukunori [Kumamoto University School of Medicine, Department of Radiology (Japan); Ono, Ken [Amakusa Medical Center, Department of Radiology (Japan); Yamashita, Yasuyuki [Kumamoto University School of Medicine, Department of Radiology (Japan)

    2005-04-15T23:59:59.000Z

    We report the utility of a combined angiography and computed tomography (angio-CT) system in assessing drug distribution to the tumor during intra-arterial chemotherapy for metastatic brain tumors in a 65-year-old man. Although digital subtraction angiography did not clearly show tumor perfusion in two cerebellar tumors, angio-CT provided definite tumor perfusion in the complicated vascular territory, and anticancer agents were infused based on its findings. To our knowledge, however, this application for intra-arterial chemotherapy of brain tumors has not been previously described.